1G, 2G, 3G, 4G

1st, 2nd, 3rd, 4th Generation (cellphone networks, sometimes transposed to G1, G2, G3 or G4)

AAA

Acronym, Anagram, Abbreviation – a term used in this list

AB

Able Bodied seaman

ABS

American Bureau of Shipping

ABT

American Bow Thruster (business name)

ABYC

American Boat & Yacht Council

AC

(1) Alternating Current

(2) Air Conditioning or Air Conditioner - sometimes written A/C

ACES

Advanced Chartworld ENC Service (trademark)

ACR

Automatic Charge Relay (relates to charging batteries)

ADLL

Admiralty Digital List of Lights

ADRS

Admiralty Digital Radio Signals

AF

Across Flats (measurement of nuts, bolts, spanners)

AGM

Absorbent Glass Mat (a type of battery)

Ah

Ampere hour (electrical, 1 Amp of current for 1 hour)

AIO

Admiralty Information Overlay

AIS

Automatic Identification System

aka

also known as

AP

Auto Pilot

APB

An NMEA0183 sentence giving course to steer, XTE and Waypoint ID

APH

Aft Pilot House

ARC

Atlantic Rally for Cruisers

ARCS

Admiralty Raster Charts Service

ARPA

Automatic Radar Plotting Aid (cf MARPA)

ASM

Application Specific Message (a type of AIS message)

ASTM

American Society for Testing Materials

ATIS

Automatic Transmitter Identification System on European inland waterways

AtN or AtoN

Aid to Navigation (occasionally presented incorrectly as ATON)

ATT

Admiralty TotalTide service

ATW

Around the World voyage of a Nordhavn 40 in 2002

AVCS

Admiralty Vector Chart Service

AWA

(1) Apparent Wind Angle

(2) Anchor Watch Alarm

AWG

American Wire Gauge (for measuring the cross section of electrical conductors)

AWS

Apparent Wind Speed

BMS

(1) Battery Management System

(2) Battery Monitoring System

BNWAS

Bridge Navigational Watch Alarm System

BPW

Bearing Position to Waypoint

BRG

Bearing (on a compass)

BSB

Base System Builder (a format for encoding data. Official NOAA raster charts conform to the BSB File Format Specification with a .kap extension)

BSOD

Blue Screen Of Death (computers)

BSP

British Standard Pipe (thread form)

BSPT

British Standard Pipe Tapered (thread form)

BST

British Summer Time

BTU

British Thermal Unit

btw

by the way

BU

Boat Unit - shorthand for (usually) USD$1,000

BUS or bus

a communication system (the term is an abbreviation of the Latin omnibus)

busbar

not an AAA; a busbar is a metallic strip or bar that conducts electricity

CAN

Controller Area Network (used originally in land vehicle technology)

CANbus

Controller Area Network bus (communications system)

CB

Circuit Breaker

CDMA

Code Division Multiple Access (for 2G cellphones, principally within USA)

CE

(1) Coastal Explorer

(2) Conformité Européenne (certification of conformity with EU regulations)

CEC

Certificate of Equivalent Competency (a term used in the UK)

CEVNI

Code Européen des Voies de la Navigation Intérieure (tr. European Code for Interior Navigation (meaning inland waterways)

cf

abbreviation of confer (Latin), meaning "compare"

CFM

Cubic Feet per Minute

CHIRP

Compressed High-Intensity Radar Pulse

CHS

Canadian Hydrographic Service

CM93 CM93/3

Distribution formats for ECNs produced by C-Map. (It is alleged that charts in the original CM93 format have been widely pirated)

CO

Carbon monoxide

Coax

Co-axial (cable)

COB

Chips on Board (type of LED)

COC

Certificate of Competency (UK)

COG

Course Over the Ground

COLREGS

International Regulations for the Prevention of Collisions at Sea

COSPAS

Cosmicheskaya Sistema Poiska Avariynyh Sudov, (Russian, tr. Space System for the Search of Vessels in Distress)

COTS

Commercial Off-The-Shelf

CPA

Closest Point of Approach

CPU

Central Processing Unit (in computers)

CTS

Course To Steer

CUBAR

Cruise Underway to Baja Rally (formerly FUBAR)

dBm

decibel-milliwatts (power ratio in decibels referenced to one milliwatt)

DC

Direct Current

Di-Chlor

Sodium Dichloro-s-triazinetrione (read this post)

DNC

Digital Nautical Chart (not an official or authoritative definition)

DHCP

Dynamic Host Configuration Protocol (computer networks)

DNV GL

a registrar and classification society

DoC

Document of Compliance

DoD

(1) Depth of Discharge (of batteries) - sometimes means the same as SoC)

(2) Department of Defence (USA) (operates the GPS system)

DPDT

Double Pole Double Throw (type of electrical switch)

DPF

Diesel Particulate Filter

DSC

Digital Selective Calling (sends a distress signal from a VHF radio)

DSM

Digital Sounder Module (in sonar displays)

DST

Daylight Saving Time (USA)

DST

Distance

DTW

Distance to Waypoint

DVI

Digital Visual Interface (for video only, no sound)

EBL

Electronic Bearing Line (on a radar screen)

EBM

Electronic Bearing Marker (on a radar screen)

ECC

Electronic Chart Centre

ECDIS

Electronic Chart Display Information System

(Full definition: An Electronic Chart Display and Information System, which, with adequate back-up arrangements, can be accepted as complying with the up-to-date chart required by regulation V/19 and V/27 of the 1974 SOLAS Convention, as

amended)

(Note: a consumer chartplotter is not an ECDIS)

ECU

Engine Control Unit

EE

Electrical Engineer

EEA

European Economic Area

eg

for example (from exemplī grātiā, Latin, full tr. "for the sake of an example")

EGC

Ethylene Glycol Coolant

EGNOS

European Geostationary Navigation Overlay Service (a type of SBAS, re. GPS)

EGT

Exhaust Gas Temperature

EIA

Electronic Industries Association

ELC

Extended Life Coolant (possibly a mere advertising puff)

ELCI

Equipment Leakage Circuit Interrupter

ENC

Electronic Navigational Chart as defined by the IHO, for use in an ECDIS
Note: a typical electronic chart sold for recreational boating use is unlikely to be an ENC because it will not comply with the S-57 standard)

EPA

Environmental Protection Agency (USA)

EPIRB

Emergency Position Indicating Radio Beacon (cf PLB)

ER

Engine Room

ESD

Electric Shock Drowning

ESS

Energy Storage Systems

ETA

Estimated Time of Arrival

EU

European Union

EULA

End User Licence Agreement

EV-DO

Evolution-Data Optimized (a telecommunications standard for 3G mobile broadband, developed in Japan)

FB

Flybridge

FDD

Frequency Division Duplex (in cellular communications)

FET

Derivation unknown. (Switches that cycle on and off in an inverter. See this post)

FI

Fuel Injection

FLA

Flooded Lead Acid (batteries)

FPH

Forward Pilot House

FPT

Female Pipe Thread

FU

Follow Up lever (for autopilots - if fitted - sometimes called a Jog lever)

FUBAR

(1) Fleet Underway to Baja Rally (2007, 9, 11, 13) - now CUBAR

(2) ...... (not for polite company)

FW

Fresh Water

fwiw

for what it's worth

fyi

for your information

G

Giga (a unit prefix in the metric system denoting a factor of a short-form billion)

G2, G3, G4

see 2G, 3G, 4G

GAGAN

GPS Aided GEO Augmented Navigation (a type of SBAS, re. GPS)

GEO

Too many meanings to list here, inc. Geo-Stationary, Geo-Synchronous, Geographic

GFCI

Ground Fault Current Interrupt (electrical safety device - aka RCD. aka GFI)

GFI

Ground Fault Interrupter (aka GFCI)

GI

Galvanic Isolator

GMDSS

Global Maritime Distress and Safety System

GMT

Greenwich Mean Time (approximately equivalent to UTC)

GNSS

Global Navigation Satellite Systems (generically, not a specific constellation)

GOC

Gear (ie: Gearbox) Oil Cooler

GPH

Gallons Per Hour (may be USG or imperial gallons)

GPRS

General Packet Radio Service (a mobile data service on 2G and 3G GSM)

GPS

Global Positioning System

GPSD

GPS Daemon (background process); sends GPS data to navigation software)

GPU

Graphics Processing Unit

GRIB

GRidded Information in Binary form (GRIB files are computer generated weather forecast files)

GSM

Global System for Mobile Communications (for 2G cellphones, principally outside USA)

GSSR

Great Siberian Sushi Run (Nordhavn cruise in company, 2009)

GT

Gross Tonnage

GUI

Graphical User Interface (computers, cf UI)

HDD

Hard Disk Drive (computers)

HDMI

High-Definition Multimedia Interface (proprietary standard audio/video interface)

HDT

An NMEA0183 sentence: True Heading

HO

Hydrographic Office

HP or hp

Horse Power

HT

(1) High Tensile (bolts) (in some countries = High Torque)

(2) High Tension (electrical leads, inc. connections to batteries & spark plugs)

HVAC

Heating, Ventilation & Air Conditioning

HYD

Hydraulic

Hz

Hertz (unit of frequency defined as one cycle per second)

IALA-AISM

International Association of Marine Aids to Navigation & Lighthouse Authorities

IBS

Integrated Bridge System

ICC

International Certificate of Competence

ID

(1) Inside Diameter (usually of a pipe, hose or tube)

(2) Identity, Identification

ie

id est (Latin, tr. "that is", also means "that is to say")

IEC

International Electrotechnical Commission

IEEE

Institute of Electrical and Electronics Engineers

IHB

International Hydrographic Bureau

IHO

International Hydrographic Organization

iirc

if I remember correctly

IMEA

International Marine Electronics Association

IMO

International Maritime Organisation

inc.

including, or included

IoT

Internet of Things (relevant to M2M)

IP

(1) Internet Protocol (the suite of protocols which enables the internet to function)

(2) Ingress protection (IEC standard 60529

IR

Infra Red

ISM

(1) International Safety Management (code)

(2) Industrial Scientific and Medical radio bands (uses include microwave ovens, cordless phones, Bluetooth devices, NFC devices, and WiFi)

ISO

International Organization for Standardization

ITRF

International Terrestrial Reference Frame (re. GPS)

ITU

International Telecommunication Union

k

kg

km

kV

kW

abbreviation of kilo, meaning one thousand

Common examples:

kilogram (or kilogramme), sometimes abbreviated as "kilos"

kilometre

kiloVolt

kiloWatt

.kap

Not an AAA. It is a file extension for the BSB format

KISS

Keep It Simple, Stupid

Kts

Knots (speed measured in NM per hour)

L or l

Litre

LAN

Local Area Network (communications, cf WAN)

LBOK

Lethal Bit Of Kit (used on the YBW motorboat forum: example)

LCD

Liquid Crystal Display

LED

Light Emitting Diode

LFP

see LiFePo4

Li....

Prefix for lithium-based battery chemistries - some (not all) are listed here

LIBS

London International Boat Show (UK – historic, defunct)

LiCoO2

Lithium Cobalt oxide battery chemistry

LiFePO4

Lithium Iron Phosphate (or Lithium Ferro Phosphate) battery chemistry

LiFeYPO4

Lithium Iron Phosphate (Yttrium based) battery chemistry

LiMn2O4

Lithium Manganese oxide battery

LiMnO2

Lithium Manganese Dioxide battery chemistry

LiNiMnCo

(1) Lithium Nickel Manganese Cobalt Oxide battery chemistry

(2) aka Lithium Manganese Cobalt Oxide battery chemistry

LLC

Limited Liability Company (in some jurisdictions only)

LLL

Load Line Length

LOA

Length Overall

LR

Lloyd’s Register of Shipping (a registrar and classification society)

LTE

Long-Term Evolution (a standard for 4G mobile communications)

LWL

Length at WaterLine (cf. LLL)

M.2

Not an AAA. A specification for internally mounted computer components

M2M

Mobile to Mobile, or Machine to Machine (in computer networks, also re. IoT)

MAC

Media Access Control address (in computer networks)

MAIB

Marine Accident Investigation Branch (UK)

MARPA

Mini- (or Manual-) Automatic Radar Plotting Aid (cf ARPA)

MBT

Manual Bus Transfer (switch)

MCA

Maritime & Coastguard Agency (UK)

MFD

Multi-Function Display (a chartplotter which can display other information)

MFDBB

Multi Function Display Black Box (computer used to operate MFDs)

MiFi

Not an AAA, this is a trade mark for a brand of wireless router

MIMO

Multiple Input, Multiple Output (devices, typically for radio frequency applications)

mm3d

Proprietary format for rendering charts, owned by Mapmedia (part of TimeZero)

MMSI

Maritime Mobile Service Identity (a number that identifies a boat on AIS & DSC)

MOB

Man Overboard

MoBo

Motor Boat

MOV

Metal Oxide Varistor ("Surge Protector")

MPPT

Maximum Power Point Tracking (in solar panel controllers)

MPT

Male Pipe Thread

MSAS

Multi-functional Satellite Augmentation System (a type of SBAS, re. GPS)

MSR

Master State Room (aka Owner's Cabin)

MTT

Multiple Transaction Translators (in computer networks)

MWD

An NMEA0183 sentence: wind direction and speed

NAS

Network Accessible Storage

N/C

Normally Closed (electrical switches) cf N/O

NFC

Near Field Communication (radio devices)

N/O

Normally Open (electrical switches) cf N/C

N2K

NMEA 2000

N2KView

Proprietary name for a product by Maretron

NAP 2017

Nordhavn Atlantic Passage 2017 (trans Atlantic cruise in company 2017)

NAPS

Nordhavns around Puget Sound

NAR

North Atlantic Rally (trans Atlantic Nordhavn motor yacht rally, held in 2004)

NAS

Network-Attached (or Accessible) storage (file-level computer data storage server)

NAT

Network Address Translation

NCM

See LiNiMnCo

NEC

National Electrical Code (USA)

NEMA

National Electrical Manufacturers Association

NFPA

National Fire Protection Association (USA)

NIC

Network Interface Card (in computing, aka network controller)

NL

Northern Lights

NM / nm

Nautical Miles

NMC

See LiNiMnCo

NMEA

National Marine Electronics Association

NMEA0183

A standard for connecting marine instrumentation, introduced in 1983

NMEA2000

Replacement for NMEA0183, date of introduction uncertain, probably 2005

NOAA

National Oceanic and Atmospheric Administration (USA)

NMVe

Non-Volatile Memory express (in computing, data storage)

NOG

Nordhavn Owners Group (private internet forum)

NPS

National Pipe Straight (USA standard thread form)

NPT

National Pipe Tapered (USA standard thread form)

NSK

Network Security Key (aka as WiFi security key, cf. PSK)

Ns

Nordhavn boats (eg: "I saw 4 Ns yesterday")

NtM

Notice to Mariners

OCP

Over Current Protection (eg; breaker, fuses)

OCPN

Open Chart Plotter Navigation

OD

Outside Diameter (usually of a pipe, hose or tube)

oeSENC

open encrypted System Electronic Nautical Chart (for use in OCPN. see SENC)

OFCOM

Office of Communications (UK)

OOW

Officer of the Watch

OP

Original Purchaser (of a boat)

Original Poster (on an internet forum)

Open CPN

See OCPN

OTG

On The Go (in full, USB OTG, a supplement to the USB specification)

PAE

Pacific Asian Enterprises (builders of Nordhavn boats)

PC

(1) Personal Computer

(2) non-boat usage, but seen on forums: Politically Correct (usually deprecatory)

PCI

PCIe

Peripheral Component Interconnect (type of computer bus)

Peripheral Component Interconnect express

PE

Potential Earth (seen on NOG forum)

PEC

Pilotage Exemption Certificate

PGC

Polypropylene Glycol Coolant

PGN

Parameter Group Number (when referring to NMEA 2000)

(NB: NMEA 0183 does not use PGNs, it uses "sentences")

PH

Pilot House (also see APH, FPH)

PLB

Personal Locator Beacon (cf EPIRB)

PLC

(1) Programmable Logic Controller

(2) Public Limited Company (UK and some other jurisdictions)

POE

Power Over Ethernet

PRN

PseudoRandom Noise number (uniquely identifies the ranging codes that a GPS satellite uses. Relevant to NMEA0183 sentences)

PS/2

Personal System 2 (a type of port used on computers for keyboards & mice)

PSK

Pre-Shared Key (in secure network connections, cf. NSK)

PST

Pacific Standard Time

PSTN

Public Switched Telephone Network

PSU

Power Supply Unit

PV

(1) Photo Voltaic (typically solar power cells)

(2) unknown usage: 43 to 55% load per the PV gauge

PWM

Pulse Width Modulation (usually in solar panel controllers)

qv

quod vide (Latin: "see which", or "refer to")

RAID

Redundant Array of Independent Disks (2 or more computer data storage devices arranged so that if one fails data is preserved_

RAINWAT

Regional Arrangement on the Radiocommunication Service for Inland Waterways (in Europe)

RAM

Random Access Memory (in a computer)

RCCB

Residual Current Circuit Breaker - same as RCD

RCD

(1) Residual Current Detector (electrical safety deviceaka GFCI )

(2) Recreational Craft Directive (applies to the EU)

RCDS

Raster Chart Display System

re.

Opinions differ. I use it to mean "regarding" or "with reference to", but that's just me.

RENC

(1) Regional Electronic Navigational Chart Centres (see ENC)

(2) Regional ENC Coordinating Centre

RIB

Rigid Inflatable Boat

RMV

Relative Motion Vector (cf TMV)

RNC

Raster Navigation Chart (official definition: 'a digital facsimile of a paper nautical chart, produced by or distributed on the authority of a government authorized hydrographic office')

RNG

Range

RNLI

Royal National Lifeboat Institution (UK and Ireland)

RO

Reverse Osmosis

RPi

Raspberry Pi (a type of PLC computer)

RPi2B

Example of a version of a Raspberry Pi, continuously evolving

RPM

Revolutions Per Minute (eg of an engine or propeller)

RS232

RS-232

(1) A standard of the Electronic Industries Association (EIA)

(2) A standard topology for a certain type of computer serial port

RYA

Royal Yachting Association (based in the UK)

S-AIS

Satellite AIS

S-52 or S52

IHO standard: Chart Content and Display Aspects of the ECDIS

(ie: standard for controlling display of ENCs in an ECDIS)

S-57 or S57

IHO standard: IHO Transfer Standard for Digital Hydrographic Data

(notation S-57 is derived from the document Special Publication No. 57 of the IHO)

(In practice S57 means ENCs supplied for use in an ECDIS)

S-61 or S61

IHO standard: Product Specification for Raster Navigational Charts (RNCs)

S-63 or S63

IHO standard: Data Protection Scheme (for ENCs used in an ECDIS)

(notation S-63 is derived from the document: Special Publication No. 63 of the IHO)

(In practice S63 means:

1. encrypted S-57 ENCs supplied for use in an ECDIS

2. other encryption schemes using the S-63 standard, eg: oeSENC charts)

S-64 or S64

IHO standard: Test Data Sets for ECDIS

SAE

Society of Automotive Engineers

SAR

Search And Rescue

SARSAT

Search And Rescue Satellite-Aided Tracking

SART

Search And Rescue Transponder

Sat

Satellite

SATA

Serial Advanced Technology Attachment (a standard for computer bus interfaces used for data storage devices)

SBAS

Satellite-based Augmentation System

SCA

Supplemental Cooling Additives

SSD

Solid State Drive (computers)

SENC

System Electronic Navigational Chart

(1) The official definition is a database, in a manufacturer's internal ECDIS format, resulting from the lossless transformation of an entire ENC contents and updates. Also see this useful source (if still available)

(2) application of the S-63 data protection scheme for electronic charts which may or may not be true ENCs, for example oeSENC charts

(3) shorthand for a system for distributing electronic charts using the S-63 data protection scheme, where those charts are not necessarily compliant with S-57

SIBS

Southampton International Boat Show (UK)

SIM

Subscriber Identity Module (in cellphones)

SLA

Sealed Lead-Acid (battery, aka VRLA)

SoC

State of Charge (of batteries - sometimes means the same as DoD)

SOG

Speed Over the Ground (cf STW)

SoH

State of Health (of batteries)

SOLAS

International convention of the IMO for Safety of Life at Sea

SOS

The international Morse code distress signal  - - -  (there is no agreement on what the letters SOS stand for)

SPDT

Single Pole Double Throw (electrical switches)

SR

State Room (aka cabin)

SSB

SingleSide Band (radio)

SSD

Solid State Drive (storage device with no moving parts in a computer)

SSH

Secure Shell, or Secure Socket Shell (network encryption protocol)

SSID

Service Set IDentifier (principally in network routers)

STCW

Standard of Training, Certification, and Watchkeeping

STW

Speed Through the Water cf SOG

SVRL or

SVRLA

Sealed Valve Regulated Lead Acid design (batteries, eg AGM)

SW

(1) South West

(2) Software (computers)

(3) Salt Water

TCP

Transmission Control Protocol (a protocol of the Internet protocol suite, cf UDP)

TCPA

Time to Closest Point of Approach (CPA)

TDC

Top Dead Centre (piston engines)

TDD

Time Division Duplex (in cellular communications)

TDMA

Time Division Multiple Access (system to allocate "slots" to AIS transmitters)

tr.

translated from one language to another

TMV

True Motion Vector (cf RMV)

TRAC

not an AAA - brand name for stabilisers made by ABT

Tri-Chlor

Trichloro-s-triazinetrione (read this post)

TSC-M

Tough Series Controller - Marine (Northern Lights proprietary product)

TSDY

TSDMY

1. Twin Screw Diesel Yacht

2. Twin screw Diesel Motor Yacht

3. Traditional Semi-Displacement Motor Yacht

4. Gin Palace (UK)

TTM

(1) Tracked Target Marker (radar)

(2) Tracked Target Message (in NMEA0183 and NMEA2000 systems)

TU

Tits Up (ie: dead)

TWA

True Wind Angle

TWD

(1) True Wind Direction

(2) True Wind Deviation (used in OCPN)

TWS

True Wind Speed

UDP

User Datagram Protocol (a protocol of the Internet protocol suite, cf TCP)

UHF

Ultra High Frequency (radio, cf VHF)

UI

User Interface (computers, cf GUI)

UK

United Kingdom of Great Britain and Northern Ireland

UKHO

United Kingdom Hydrographic Office

UMTS

Universal Mobile Telecommunications System (for cellphones)

USA

United States of America

USB

(1) Universal Serial Bus (in computers)

(2) U****** S** o* a B**** (not for polite company)

USCG

United States Coast Guard

USD

United States Dollar

USG

United States Gallon (=3.78541178 L, 0.83267382 Imperial Gallon)

UTC

Temps Universel Coordonné (time measured by an atomic clock. Approximately equivalent to GMT)

UV

Ultra Violet (used re. lighting and water treatment)

UTM

Unified Threat Management (network security implemented at a single point)

VAT

Value Added Tax

VAtoN

Virtual Aid to Navigation

VCG

Vertical Centre of Gravity

VDR

(1) Voyage Data Recorder

(2) Vessel Data Recorder (proprietary name for a product by Maretron)

VFD

Variable Frequency Drive (for controlling electrical current)

VGA

Video Graphics Array (in computers)

VHF

Very High Frequency (radio, cf UHF)

VLCC

Very Large Crude (oil) Carrier

VMH

Visit My Harbour (UK navigation website and supplier of charts)

VoLTE

Voice over LTE (a standard enabling mobile phones to connect over the internet)

VPN

Virtual Private Network (computing)

VRLA

Valve-Regulated Lead-Acid (battery, aka sealed lead-acid (SLA), gel cell, or maintenance free battery)

VRM

Variable Range Marker (radar)

VSAT

Very Small Aperture Terminal (a type of two-way satellite ground station)

VTS

Vessel Traffic Services (in controlled waters)

VWT

An NMEA0183 sentence = TWS

WAAS

Wide Area Augmentation System (a type of SBAS, re. GPS)

WAN

Wide Area Network (in electronic communications, cf LAN)

WCDMA

Wideband Code Division Multiple Access (a telecommunications standard for 3G mobile broadband, developed in USA)

WEP

Wired Equivalent Privacy (an insecure predecessor of WPA)

WGS 84

World Geodetic System of 1984 (re. GPS)

Wi-Fi

WiFi

Not an AAA, a trademark of the Wi-Fi Alliance.

A technology for wireless LANs based on the 802.11 standards of the IEEE

WOT

Wide Open Throttle

Wp

Watts peak (in solar panel technology)

WPA, WPA2

Wi-Fi Protected Access (encryption standards)

WPS

Wi-Fi Protected Setup (encryption standard described as "seriously flawed")

XMFR

Transformer

XTE

Cross Track Error (in navigation, including equipment. Also an NMEA0183 sentence)

XW

Cross Wind (wind direction different to boat heading)

YMMV

Your Mileage May Vary

Z (or Zulu)

Military time zone equivalent to UTC