ABS:
Acrylonitrile-Butadiene-Styrene

AISI:
American Iron and Steel Institute

all-thread:
Threaded rod from end to end available in various metals, lengths and sizes

ANSI:
American National Standards Institute

ASME:
American Society of Mechanical Engineers Provides boiler and pressure vessel codes used throughout the USA and most other countries

ASTM:
American Society for Testing and Materials

AWG:
American Wire Gauge

AWS:
American Welding Society

b.c.:
Bolt Circle

CFM:
Cubic Feet per Minute

CNC:
Computer Numerical Control

Co:
Cobalt - as used in bits (not to be confused with CO)

CO:
Carbon Monoxide

DCEN:
Direct Current Electrode Negative

DCEP:
Direct Current Electrode Positive

DOF:
Degrees of Freedom

DSAW:
Double Submerged Arc Welding

DWV:
Drain Waste Vetilation

ECM:
Electro Chemical Machining

EDM:
Electrical Discharge Machining

FDM:
Fused Deposition Modeling

FPS:
Feet Per Second

FPT:
Female (internal) NPT thread

GDT:
Geometric Dimensioning and Tolerancing

GMAW:
Gas Metal Arc Welding also known as MIG welding

GTAW:
Gas Tungsten Arc Welding also known as Heliarc and TIG welding

IC:
Indexable Carbide Integrated Circuit Internal Combustion

ID:
Inside Diameter

IPS:
Inches Per Second

ISO:
International Organization for Standardization

ITI:
Industrial Technology Institute

JIS:
Japanese Industrial Standards

LBC:
Laser Beam Cutting

LBW:
Laser Beam Welding

LH:
Left Hand (as in thread)

LMC:
Least Material Conditon Used in geometric tolerancing

LOM:
Laminated Object Modeling

MAP:
Manufacturing Automation Protocol

MIG:
Metal Inert Gas welding process

MMC:
Maximum Material Condition Used in geometric tolerancing

MOSFET:
Metal Oxide Semiconductor Field Effects Transistor

MPT:
Male (external) NPT thread

MT:
Morse Taper, usually followed with a number; 0, 1, 2, etc.

MTBF:
Mean Time Between Failures

MTTF:
Mean Time To Failure

MTTR:
Mean Time To Repair

MWP:
Maximum Working Pressure

NC:
Numeric Control

NEMA:
National Electrical Manufacturer's Association

NPS:
Nominal Pipe Size

NPS:
National Pipe Straight

NPT:
National Pipe Thread

NPTF:
Dryseal American National Standard Taper Pipe thread

OD:
Outside Diameter

OEM:
Original Equipment Manufacturer

PAC:
Plasma Arc Cutting

PAW:
Plasma Arc Welding

PSI:
Pounds per Square Inch

PSIA:
Pounds per Square Inch Absolute

PSIG:
Pounds per Square Inch Gauge

PTFE:
Polytetrafluroethylene polymer Teflon is DuPont trademark for PTFE

QC:
Quick Change - referring to drive gears for a lathe or mill

RA:
Rockwell Hardness "A" Scale

RB:
Rockwell Hardness "B" Scale

RC:
Rockwell Hardness "C" Scale

RD:
Rockwell Hardness "D" Scale

RFS:
Regardless of Feature Size Used in geometric tolerancing

RH:
Right Hand (as in thread)

RP:
Rapid Prototyping

RPM:
revolutions per minute

RPS:
Revolutions Per Second

RTL:
Resistor-Transistor Logic

SAE:
Society of Automotive Engineers

SCFM:
Standard Cubic Feet per Minute

SFM:
Surface Feet per Minute

SLS:
Selective Laser Sintering

SMAW:
Shielded Metal Arc Welding

SME:
Society of Manufacturing Engineers

STL:
Stereo Lithography

SW:
Stud Arc Welding`

TIG:
Tungsten Inert Gas welding process

TIR:
Total Indicator Reading

TPI:
Threads Per Inch

TSP:
Trisodium Phosphate used in metal cleaning

TTL:
Transistor-transistor logic - form of electronic logic

UL:
Underwriter's Laboratory

UNC:
Unified Coarse - referring to threads

UNEF:
Unified Extra Fine Thread

UNF:
Unified Fine - referring to threads

WP:
Working Pressure