ABS

Anti-Lock Braking System, the feature which allows you to retain the ability to directionally control your vehicle during emergency deceleration.

AC

All modes of conditioning air inside the passenger area of the vehicle:  Heating, Cooling, Venting

A/C

Condensing of air to cool it and to remove humidity.

Assist

Hybrid system with a small battery-pack and a single small electric-motor that provides peak power for the gasoline-engine during periods of acceleration.

AT-PZEV

Advanced Technology - Partial Zero Emission Vehicle

BAS

Belt-Alternator System – GM’s assist hybrid technology

"B" Mode

Engine Braking, (it isn't actually a gear) when you shift the transmission to this setting the engine will be used to slow down the car, it works similar to an exhaust brake used on the large semi-trucks (except the one on Prius is totally silent).

C

Celsius, a measure of temperature, (C * 1.8) + 32 = F,  -25°C = -13°F,  -15°C = 5°F,  -5°C = 23°F, 
0°C = 32°F,  5°C = 41°F,  20°C = 68°F,  25°C = 77°F,  30°C = 86°F

CAFE

Corporate Average Fuel Economy, the US system used to measure overall fleet efficiency

CARB

California Air Resources Board, an agency dictating emissions requirements for cars sold in California. (These are often more strict than Federal standards.)

CAT

Catalytic Converter, a vital component in the emissions system, typically utilizing a self-renewing metal

CC

Cruise Control

Cd

Coefficient of drag (0.29 for the Original & Classic Prius, 0.26 for the Iconic Prius)

CEL

Check Engine Light

Classic

The term used to identify the 2001 - 2003  model years of Prius.

CNG

Compressed Natural Gas

CO2

Carbon-Dioxide, the type of vehicle emission that contributes to global warming.

CVT

Continuously Variable Transmission, Prius uses the "Planetary" design which functions as a power-split device to manage multiple sources of thrust; other CVT vehicles use a "Cone & Belt" design to adjusts power ratios.

Dinosaur

A very large, gas-guzzling, high-emission vehicle based on 20th century technology… doomed to extinction.

DRL

Daytime Running Lights

DVD

Digital Versatile Disc, used for the Navigational system in Prius

E10

Blended engine fuel, 10% ethanol and 90% gasoline

E85

Blended engine fuel, 85% ethanol and 15% gasoline

ECU

Electronics Control Unit, the amazing computer that monitors and controls the two motor-generators, the gas engine, the motion of the planetary gear set, the battery pack power levels etc. to provide the Prius' smooth acceleration and speed control.

Engine

The term used to refer to the device which runs on gasoline, utilizing combustion to push pistons to deliver power.

EPA

Environmental Protection Agency, the group responsible for rating the emissions & efficiency of vehicles sold in the United States.

EV

Electric Vehicle, powered exclusively by a battery-pack charged before use

F

Fahrenheit, a measure of temperature, (F - 32) / 1.8 = C,  -15°F = -26.11°C,  0°F = -17.78°C,  15°F = -9.44°C,  32°F = 0°C,  40°F = 4.44°C,  60°F = 15.56°C,  70°F = 21.11°C,  80°F = 26.67°C

FCHV

Fuel Cell Hybrid Vehicle, a fuel-cell vehicle that takes advantage of hybrid technology including the use of a battery-pack

FOB

The device (introduced in 2003) used to unlock doors and start the hybrid system.  By default, it works as a wireless remote for unlocking and is inserted into a slot in the dashboard for starting.  As an option, it can be upgraded to control the SKS (formally known as SE/SS) feature.  And note that there is actually a traditional key within which can be used for unlocking the driver's door manually.

FUD

Fear, Uncertainty, Doubt

Full

Hybrid system with a large battery-pack, a small electric-motor, at least one large electric-motor, and a gasoline-engine that combined provide a wide variety of combustion & electric propulsion abilities.

GPS

Global Positioning System, this is the part of the Prius Navigation System that identifies your exact location on Earth.

Greenwash

To intentionally mislead with respect to environmental benefits.

HEV

Hybrid Electric Vehicle

HID

High Intensity Discharge, bulbs used for headlights; illumination is created using an arch electricity instead of a traditional filament

HSD

Hybrid Synergy Drive - Toyota's modular hybrid design, implemented starting with the 2004 Prius with other vehicles now also using it.

HOV

High Occupancy Vehicle - used to describe the restricted "diamond" lanes on highways

HP

Horsepower, indicating a unit of power, a measurement different from torque

ICE

Internal Combustion Engine

Iconic

The term used to identify the 2004 - 2009 model years of Prius.

IMA

Integrated Motor Assist - Honda's hybrid technology

km

Kilometer, a measure of distance, 1 kilometer is equal to 0.6214 mile

kW

Kilowatt, an electrical measurement unit used when describing Prius power consumption & storage

LEV

Low Emission Vehicle, once the cleanest designation, but no surpassed by several levels of reduced emissions

L/100km

Liters per 100 kilometers, the more common unit of efficiency measurement outside of the US and UK

LMPG

Lifetime Miles Per Gallon

LRR

Low Rolling Resistant - used to describe minimum friction tires

MD

Multi-Display - the touch-sensitive liquid-crystal screen on the dashboard of Prius

Mi

Mile, a measure of distance, 1 mile = 1.6093 kilometers

MG

Motor Generator, an electric motor which can either provide motive power when electrically driven or generate electricity when mechanically driven.

MG1

The smaller Prius electric motor.  It is three-phase AC permanent-magnet synchronous motor/generator starts the ICE, controls the CVT, and generates the electricity (by using thrust from the ICE and deceleration power from slowing before the brake-pedal is pushed) to charge the battery-pack and/or feed the larger motor. 

MG2

The larger Prius electric motor.  It is three-phase AC permanent-magnet synchronous motor/generator drives the wheels and generates electricity (from regenerative braking) to recharge the battery-pack.

Motor

The common term used to refer to the power device which operates using electricity.

MPG

Miles Per Gallon

MSRP

Manufacturer's Suggested Retail Price

MY2001

Model Year 2001 (which became available in the United States the summer of 2000)

NAV

DVD-based GPS Navigation System, used in Prius

NiMH

Nickel-Metal Hydride, the type of modules used in the Prius battery-pack

NOx

Nitrogen Oxides, that type of vehicle emission that contributes to smog

NVH

Noise, Vibration, Harshness

OEM

Original Equipment Manufacturer, components directly from the automaker

OPEC

Organization of the Petroleum Exporting Countries

Original

The term used to identify the 1998 - 2000 model years of Prius (which were only available in Japan).

Priustoric

All that transpired before the Prius

PHEV

Plug-In Hybrid Electric Vehicle

PPM

Parts Per Million, the scale at which emissions are common measured, literally a count of matter within a unit

PSD

Power-Split Device, the planetary gear set which divides power between the ICE and the two electric motor-generators, also functions as the continuously-variable transmission.

PZEV

Partial Zero Emission Vehicle.  (A manufacturer must eliminate evaporative emissions and ensure that the vehicle will run cleanly for its entire projected life.  Even if the vehicle is just sitting in the driveway, it is still polluting.  The source of this pollution is hydrocarbons emitted from the gas tank as gasoline slowly evaporates.  To achieve PZEV certification, all evaporative emissions must be eliminated.)

R&D

Research & Development

SE

SKS:  Smart-Entry.  It is a proximity detection system that automatically senses a wireless transmitter (called a "fob") in your pocket or purse, allowing you to unlock the doors & hatch without the need to use a physical key or push a button on a remote.

SKS

Smart-Key-System (formally known as SE/SS: Smart-Entry & Smart-Start).  It is the collective term used to describe all features of the wireless system available with some models of Prius.

SOC

State Of Charge,  indicating the amount of stored electricity available in the battery-pack

SS

SKS:  Smart-Start.  It is proximity detection system that automatically senses a wireless transmitter (called a "fob") in your pocket or purse, allowing you to start the hybrid system without the need to use a physical key or push a button on a remote.

Stealth

Electric-Only driving (up to 42 MPH for Classic & Iconic Prius) without the engine in motion.

SRS

Supplemental Restraint System, better known as Airbags

SULEV

Super Ultra Low Emission Vehicle (only a few vehicles qualify for this clean rating category, Prius is among them)

THS

Toyota Hybrid System - Toyota's hybrid design for the Classic Prius

Torque

Measurement value indicating wheel turning force, a strength value different from horsepower

TRAC

Toyota Rent-A-Car, a program by which some have shortened the waiting time: when the demo/rental units reach a time/mileage it permits the dealer to sell them.

Turtle

Driving a Classic Prius with the battery-pack extremely drained of electricity, in conditions too hot (typically above 105 F degrees), or conditions too cold (typically below -10 F degrees), so that an orange "turtle" icon displays near the speedometer.  This warns the driver to avoid forceful acceleration.

Two-Mode

GM’s full hybrid technology

ULEV

Ultra Low Emission Vehicle (as of the 2003 model-year there were 90 vehicle models in the United States that met the rating criteria)

V

Volt or Voltage, an electrical measurement unit used when describing attributes of Prius propulsion components.

VIN

Vehicle Identification Number, the worldwide identifier unique to each vehicle ever built

Vaporware

A term from the computer industry used to describe claims made by a company about a product that was never delivered.  It sounded great in concept, but for whatever reason was impractical in the end.  In other words, don't believe it until you actually see the product available for consumers to purchase.

VSC

Vehicle Stability Control, a safety feature that automatically engages side-specific braking for you when it detects the vehicle wheels slip; stepping on the brake is not necessary for the feature to work

ZEV

Zero Emission Vehicle