Abbreviations

A-Z guide for common abbreviations.

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

A

A Ampere or anode
a.c. Alternating current
a.f. Audio frequency
a.f.c. Automatic frequency control
a.g.c. Automatic gain control
a.m. Amplitude modulation
A.S.A. American Standards Association
a.t.u. Aerial tuning unit
a.v.c. Automatic volume control
A/D Analogue to digital
A/F Across Flats - width of nut/bolt etc.
abs Absolute
ABS Acrylonitrile Butadiene Styrene
ACK Acknowledge
ADC Analogue to digital converter
ADSL Asymmetrical Digital Subscriber Line
Ae Aerial
Ag Silver (Chemical Symbol)
Ah Ampere Hour
Al Aluminium (Chemical Symbol)
amp Ampere
ANSI American National Standards Institute
Ar Argon (Chemical Symbol)
ARCNet Attached Resource Computer Network
As Arsenic (Chemical Symbol)
ASCII American Standard Code for Information Interchange
ASK Amplitude shift keying
ASTA Association of Short Circuit Testing Authorities
ASTM American Society for Testing and Materials
ATE Automatic Test Equipment
atm Atmosphere
ATM Asynchronous Transfer Mode
Au Gold (Chemical Symbol)
AUI Attachment Unit Interface (15 way 'D' Connector)
AUX Auxiliary
AV Audio Visual
AWG American Wire Gauge
AWM Appliance Wiring Material

B

b Base of transistor
b.p.s. Bits per second
BA British Association (type of screw thread)
BAF Bonded acetate fibre
BASEC British Approval Service for Electrical Cables
BASEEFA British Approvals Service for Electrical Equipment in Flammable Atmospheres
Be Beryllium (Chemical Symbol)
BEAB British Electrotechnical Approvals Board
BFA British Federation of Audio
BGA Ball Grid Array
BMP Bit Map
BNC Bayonet Neill-Concelman (co-ax connector, named after the inventors)
BP Bulk Pack
bpm blows per minute
BPO British Post Office
BR Bass reflex
BS British Standard
BSI British Standards Institution
BSP British Standard Pipe (type of screw thread)
BSPT BSP Taper thread
btu British Thermal Unit

C

C Capacitor, cathode, centigrade, Celsius, coulomb
c Collector of transistor, speed of light, centi
CAD Computer Aided Design
CAM Computer Aided Manufacturing
CAT Category
CB Citizens Band ( Amateur Radio )
cc cubic centimetre
CCD Charge coupled device
CCITT International Telegraph and Telephone Consultative Committee ( French Acronym)
CCTV Closed Circuit Television
cd Candela
CD Compact Disk
CDM Construction Design & Management ( regulations )
CENELEC Comite European de Normalisation
CERDIP Ceramic Dual In-line Package
CETOP Comite European des Transmissions Oleohydrauliques et Pneumatiques
CFC Chlorofluorocarbon
cfm cubic foot per minute
CHIP Chemical Hazard Information Profile
chps Characters per second
Chr Character
CIM Computer Integrated Manufacturing
CLK Clock signal
CMA Cable Manufacturers Association
CMOS Complementary metal oxide semiconductor
CNC Computer Numerical Control
cNm centi Newton metre
Co-ax Co-axial (sharing the same axis)
col column
COM Communications Port
COS Cosine
COSHH Control Of Substances Hazardous to Health (regulations)
cpi characters per inch
cps characters per second
CPU Central processor unit
Cr Chromium
CrO2 Chromium dioxide
CSA Canadian Standards Association
csa Cross Sectional Area
CSP Chlorosulphonated Polyethylene
cSt centi Stokes
CTD Charge transfer device
CTFE Chlorotrifluoroethylene
Cu Copper

D

D Diode
d Drain of an f.e.t.
d.c. Direct current
D/A Digital to analogue
DAC Digital to analogue converter
daN Deca Newtons
DAP Di allyl Phthallate
dB Decibel
DCC Double cotton covered
DCE Data circuit-terminating equipment
DEC Digital Equipment Corporation
DEF STAN Defence Standard ( UK )
DEG Degrees
DES Data Encryption Standard
DF Direction finding
Dia. Diameter
DIL Dual-in-line
DIMM Dual In-line Memory Module
DIN Deutsche Industrie Norm
DIP Dual In-line Package
DMA Direct memory access
DMM Digital Multimeter
DOL Direct on Line
DPCO Double Pole Change-Over -contact arrangement
DPDT Double pole, double throw
dpi Dots per inch
DPM Digital Panel Meter
DPST Double pole, single throw
DTE Data terminal equipment
DTL Diode-transistor
DTMF Dual tone multi-frequency
DVM Digital Volt Meter
DX Long distance reception

E

e Emitter of transistor
e.h.t. Extremely high tension (voltage)
e.m.f. Electromotive force
EAROM Electrically alterable read only memory
ECC Earth Continuity Conductor
ECL Emitter coupled logic
ECR Electronic Cash Register
EEPROM Electrically erasable programmable read only memory
EGA Enhanced Graphics Adapter
EIA Electronic Industries Alliance
EISA Extended Industry Standard Architecture
EMC Electro Magnetic Compatibility
EMI Electro Magnetic Interference
EMP Electro Magnetic Pulse
EN Euro Norm - standard
EPDM Ethylene Propylene Diene Rubber
EPOS Electronic Point of Sale
EPR Ethylene Propylene Rubber
EPROM Erasable programmable read only memory
EQ Equalisation
EROM Erasable read only memory
ERP Effective radiated power
ESD Electrostatic Discharge
EVA Ethyl Vinyl Acetate, Ethyl Vinyl Alcohol
EXP Exponential

F

F Farad, Fahrenheit or force
f Frequency
F.C. Fixing Centres
f.e.t. Field effect transistor
f.m. Frequency modulation
f.r. Frequency response or range
f.s.d. Full scale deflection
f.s.k. Frequency shift keying
FBLT Fibre Bend Limiting Tubing
FCC Federal Communications Commission
FDA Federal Drug Administration
FDDI Fibre Distributed Data Interface
FDDI Fibre Distributed Data Interface
Fe Ferrous
FeCr Ferro-chrome
FEP Fluorinated Ethylene Propylene
FFC Flat Flexible Cable
FRP Flame Retarded Polyethylene
FTP File Transfer Protocol
FTP Foil (screened) Twisted Pair cable

G

G Giga (10g)
g Grid, gravitational constant, gram ( unit of mass)
G Parallel thread
GHz Giga Hertz
GIF Graphics Interchange Format
GLS General Lighting Service
GM Geiger-Mueller (gamma ray detector)
GOST Gosudarstvenii Standart (Russian Standards)
gr grain ( unit of mass)
GRP Glass Reinforced Plastic

H

H Henry
h Hour
h.f. High frequency
HBC High Breaking Capacity
HCFC HydroChlorofluorocarbon
HDPE High Density Polyethylene
HEX Hexagonal
Hg Mercury
HOFR Heat Resistant, Oil Resistant, Flame Retardant
hr Hour
HRC High Rupture Capacity
HRC Hardness on the Rockwell C scale
HSE Health and Safety Executive
HSS High Speed Steel
HT High Tension
HTML Hyper Text Mark-up Language
HVAC Heating, Ventilation & Air Conditioning
Hz Hertz (cycles per second)

I

I Current
i.c. Integrated circuit
i.m.d. Intermodulation distortion
i.p.s. Inches per second
I/O Input / Output
i/p Input
I/P Current to Pressure converter
I²L (IIL) Integrated injection logic
IB Infinite baffle
ID Identity
IDC Insulation Displacement Connector
IDT Insulation Displacement Technology
IEC The International Electrotechnical Commission
IEE The Institution of Electrical Engineers (UK)
IEEE The Institute of Electrical & Electronic Engineers (USA)
IF Intermediate frequency
IMQ Instituto Italiano del Marchio di Qualita
in inch (unit of Length )
in wg Inches Water Gauge
IP Ingress Protection ( IEC standard )
IPA Iso Propanol Alcohol
ISA Industry Standard Architecture
ISDN Integrated Services Digital Network
ISO International Standardisation Organisation
ITU International Telecommunications Union

J

J Joule
JEDEC Joint Electron Defence Engineering Council
JEIDA Japanese Electronics Industry Development Association
JIS Japan Industrial Standards Committee
JPEG Joint Photographic Experts Group

K

k Kilo (10³) or cathode
K Kilo, in computing terms (= 210=1024), or degrees Kelvin
K Kelvin
KEMA Netherlands Test Agency
kg kilogram
kv/mm kilo volts per millimetre ( dielectric strength )

L

L Inductance or lumens
l.e.d. Light emitting diode
l.f. Low frequency
l.w. Long wave (approx. 1100-2000m)
l/m litres per minute
L/min litres per minute
l/s litres per second
LAN Local Area Network
lb Pound (weight unit)
lbf Pounds of force
lbf in Pounds of force per inch
LCD Liquid Crystal Display
LDPE Low Density Polyethylene
LIN Linear
LOG Logarithmic
LS Loudspeaker
LSF Low Smoke & Fume
LSI Large scale integration
LSOH Low Smoke, Zero Halogen
LVD Low Voltage Directive
LVDT Linear Variable Differential Transformer

M

M Mega (106)
m Milli (10-³) or metres
m metre
m.c. Moving coil
m.w. Medium wave (approx. 185-560m)
mA milliamp
mAh milli Ampere Hour
MAN Metropolitan Area Network
Mb Mega byte
Mbits/sec Megabits per second (million bits per second)
MCA Micro Channel Architecture
MCB Miniature Circuit Breaker
mcd milli candela
MCSD Microsoft Certified Solution Developer
MCSE Microsoft Certified Systems Engineer
MF Melamine Formaldehyde
MFD micro Farad
MHz Megahertz
MI Musical Instrument
mic Microphone
MIC Mineral Insulated Cable
MIDI Musical Instrument Digital Interface
MIG Metal Inert Gas
Mil Length unit, 0.001 inch
MIL STD Military Standard
ml milli litre
mm wg millimetres water gauge
MMJ Modified Modular Jack
MOD Ministry of Defence
MOS Metal oxide semiconductor
MOV Metal Oxide Varistor
MPEG Moving Pictures Expert Group
MPU Microprocessor unit
MPX Multiplex
MSCP Mean Spherical Candle Power
MTA Mass Termination Assembly
MUSA Multiple Unit Steerable Antenna
mV milli Volt
mW milli Watt

N

n Nano (10 - 9)
N Newton
n/c Not connected; normally closed
n/o Normally open
Na Sodium
NAMAS National Measurement Accreditation Service
NASA National Aeronautical and Space Administration
NATO North Atlantic Treaty Organisation
Ncm Newton centimetre
NEC National Electrical Code
NEMA National Electrical Manufacturers Association
NEMKO Norges Elektriske Materiellkontroll
NFPA National Fire Protection Agency
Ni Nickel
NIC Network Interface Card
Ni-Cad Nickel-cadmium
NICAM Near Instantaneously Companded Audio Multiplexed
NiMH Nickel-Metal Hydride
Nm Newton Metre
NMOS Negative channel metal oxide semiconductor
NOS Network Operating System
NPN Negative, Positive, Negative ( Transistor )
ns Nano second
ns/m Nano second per metre
NTC Negative Temperature Coefficient
NTSC National Television System Committee
NVP Nominal Velocity of Propagation

O

o.d. Outside Diameter
o/c Open channel; open circuit
o/p Output
OEM Original Equipment Manufacturer
OFC Oxygen Free Copper
OFTEL Office of Telecommunications
OHP Over Head Projector
OHT Over Head Transparency
op-amp Operational amplifier
OTDR Optical Time Domain Reflectometer
OVE Osterreichischer Verban Fur Elektrotechnik

P

p Pico (10 - 12)
p.a.m. Pulse amplitude modulation
p.r.f. Pulse repetition frequency
PA Public address
PA Poly Amide (Nylon)
PABX Private automatic branch exchange
PAL Phase alternation, line
PAL Phase Alternating Line
PAT Portable Appliance Tester
PBT Polybbutylene Terephthalate
PBX Private branch exchange
PC Poly Carbonate
pc piece
PCB Printed circuit board
pce piece
PCI Peripheral Component Interconnect
PCM Pulse code modulation
PCMCIA Personal Computer Memory Card International Association
PCP PolyChloroprene (Neoprene)
PCTFE Poly Chloro Tri Fluoro Ethylene
PCW Plain Copper Wire
Pd Palladium
PDF Portable Document Format
PE Polyethylene
pF Pico Farad
pF/m Pico Farad per metre
PG Panzerrohr Gewinde ( Conduit Thread )
pH Potential of Hydrogen
PICMG PCI Industrial Computer Manufacturers Group
PIDG Pre-Insulated Diamond Grip
PLA Programmable logic array
PLC Programmable Logic Controller
PLL Phase locked loop
PMOS Positive channel metal oxide semiconductor
PNG Portable Network Graphics
PNP Positive, Negative, Positive (Transistor)
POS Point of Sale
PP Polypropylene
ppm Parts per Million
PPO Polyphenylene Oxide
PROM Programmable read only memory
PRT Platinum Resistance Thermometry
PS Polystyrene
PSI pounds per square inch
PSS Packet SwitchStream
PSTN Public Switched Telephone Network
PSU Power supply unit
Pt Platinum
Pt100 Platinum Resistance Temperature Probe
PTB Physikalisch Technische Bundesanstalt (German Test Agency)
PTC Positive Temperature Coefficient
PTFE Poly Tetra Fluoro Ethylene
PU Pickup
PUJT Programmable unijunction transistor
PUR Polyurethane
PVC Poly Vinyl Chloride
PVDF Poly Vinylidine Fluoride
PWM Pulse Width Modulation

Q

Q Quality factor; efficiency of tuned circuit, charge
QA Quality Assurance
QFP Quad Flat Pack (IC package)

R

R Resistance
r.f. Radio frequency
r.f.c. Radio frequency choke (coil)
r.m.s. Root mean square
R/A Right Angle ( 90 degree )
R/W Read/write
RAD Radians
RAM Random access memory
RCA The Radio Corporation of America
RCD Residual Current Device
RCF Recommended crossover frequency
RFI Radio Frequency Interference
RG Radio Grade (cable)
RIAA Recording Industries Association of America
RIDDOR Reporting of Injuries, Diseases & Dangerous Occurrences Regulation(s)
RJ Registered Jack
RMA Rosin, Mildly Activated
ROM Read only memory
rpm revolutions per minute
RSJ Rolled Steel Joist
RTC Resistive Temperature Compensation
RTC Real Time Clock
RTL Resistor transistor logic
RX Receiver

S

S Siemens
S Source of an f.e.t.
s Second (unit of Time)
s.h.f. Super high frequency
s.w. Short wave (approx. 10-60m)
s.w.g. Standard wire gauge
s.w.r. Standing wave ratio
s/c Short circuit
S/N Signal-to-noise
SAE Society of Automotive Engineers
SCART Syndicat des Constructeurs d'Appareils Radio Recepteurs et Televiseurs
SCR Silicon-controlled rectifier
SCSI Small Computer Systems Interface
SEMKO Svenska Elektriska Materielkontrollanstalten
SEV Schweizerischer Elektrotechnischer Verein
SI International system of units
SIM Subscriber Identity Module
SIMM Single in-line Memory Module
SIN Sine
SMA Sub-Miniature 'A' (co-ax connector)
SMB Sub-Miniature 'B' (co-ax connector)
SMC Sub-Miniature 'C' (co-ax connector)
SMD Surface Mount Device
SMT Surface Mount Technology
SNA Systems Network Architecture
SNMP Simple Network Management Protocol
SOD Small Outline Device
SOIC Small Outline Integrated Circuit
SOT Small Outline Transistor
SPDT Single pole, double throw
SPL Sound pressure level
spm strokes per minute
SPST Single, pole, single throw
SSI Small scale integration
STP Screened Twisted Pair Cable
SVGA Super Video Graphics Adapter
SWA Steel Wire Armoured
SWL Safe Working Load

T

T Tesla
t.r.f. Tuned radio frequency
TACW Tinned Annealed Copper Wire
TAN Tangent
TC Trade Counter
TCP/IP Transmission Control Protocol/ Internet Protocol
TCW Tinned Copper Wire
TDM Time division multiplex
TDR Time Domain Reflectometry (Pulse echo test for impedance mismatch)
TFE Tetrafluroethylene
TIA Telecommunications Industry Association
TIF Tagged Image File
TNC Threaded Neill-Concelman (co-ax connector, named after the inventors)
TPE Thermoplastic Elastomer
TPI Threads per inch
TPI Tracks per inch
TPI Teeth per inch
TQM Total Quality Management
TR Transformer
TTL Transistor transistor logic
TWA Time Weighted Average
TX Transmitter

U

UART Universal asynchronous receiver transmitter
mH micro Henries
mH/m micro Henries per metre
U 19inch rack, Height unit, (1.75 inch / 44.45mm)
u.h.f. Ultra high frequency (approx. 470-854MHz)
u.j.t. Unijunction transistor
UF Urea Formaldehyde
UL Underwriters Laboratory
ULA Uncommitted logic array
UNC Unified National Coarse (thread)
UNF Unified National Fine (thread)
USB Universal Serial Bus
UTP Unscreened Twisted Pair cable
UV Ultra Violet

V

V Volts
VA Volt-amps
v.c.a. Voltage controlled amplifier
v.c.o. Voltage controlled oscillator
VCT Voltage to current transactor
v.h.f. Very high frequency (approx. 88-216 MHz)
v.l.f. Very low frequency
VU Volume unit
VGA Video Graphics Array
VDE Verband Deutscher Elektrotechniker
VHS Video Home System
VSWR Voltage Standing Wave Ratio
VESA Video Electronics Standards Association.
VDU Visual Display Unit
VME Versa Module Eurocard
VCR Video Cassette Recorder
VOC Volatile Organic Compound

W

W Watts
w.p.m. Words per minute
W/F Wow and flutter
W/m watts per metre
WAN Wide Area Network
Wb Weber
WDM Wavelength Division Multiplexing
WG Water Gauge
WKG Working
WYSIWYG What you see is what you get

X

X Reactance
XLPE Cross Linked Polyethylene

Y

Sorry but we currently have no Y's

Z

Z Impedance
ZD Zener diode
ZIF Zero Insertion Force