1. Acting or operating in a manner essentially independent of external influence or control; such as, an automatic light switch; a budget deficit that triggered automatic spending cuts.
2. Self-regulating; for example, an automatic washing machine.
3. Acting or done without volition or conscious control; involuntary; spontaneous; for example, automatic shrinking of the pupils of the eyes in strong light.
4. Acting or done as if by machine; mechanical; such as, an automatic reply to a familiar question.
5. Capable of firing continuously until ammunition is exhausted or the trigger is released; as with, an automatic rifle.
6. Semiautomatic; an automatic pistol.

The words automatic pilot or automatic transmission bring to mind mechanical devices that operate with minimal human intervention. Yet the word automatic, which goes back to the Greek word automatos, “acting of one's own will, self-acting, of itself,” is made up of two parts, auto-, “self,” and -matos, “willing,” is first recorded in English in 1748 with reference to motions of the body; such as, the peristaltic action of the intestines: “The Motions are called automatic from their Resemblance to the Motions of Automata, or Machines, whose Principle of Motion is within themselves.”

Although the writer had machines in mind, automatic could be used as a reference to living things, a use we still have. The association of automatic chiefly with machinery may represent one instance of many in which we have come to see the world in mechanical terms.

1. To select key words from a document, commonly by an automatic or machine method, for the purpose of forming an abstract of the document.
2. A proces of automatically selecting key words and phrases which represent the basic content of a document; often using statistical or counting techniques.
3. The material abstracted from a document by machine methods.

1. A complete receiving, selecting, and warning device capable of being actuated automatically by intercepted radio-frequency waves forming the international automatic alarm signal.
2. A component of an international network of alarm receivers actuated by a radio-frequency signal to indicate an international emergency.

1. The automatic dialing of a telephone number by a computer or an automatic calling unit.
2. The automatic placing of a telephone call by a computer or a computer-controlled modem.

The process of using a computer to convert automatically a symbolic code into a machine code.

A broad term that covers methods of collecting data and entering it directly into computer systems without human involvement.

Technologies normally considered part of auto-ID include bar codes, biometrics, and voice recognition.

1. Automatic data processing by electronic means without the use of tabulating cards or punched tapes.
2. The processing data by using equipment which is predominantly electronic in nature; such as, an electronic digital computer in recording, classifying, summarizing, and manipulating data.
3. The use of electronic memories to store, to up-date, and to read information automatically, and using that information in accounting, filing, etc.; including any computerized information system and the equipment used in that system.
4. Any data processing that is done primarily on electronic equipment.

It usually refers to data which is performed and processed on digital computers.

1. A circuit or device that produces a nearly constant voltage output, even when the voltage input (line) and current output (load) may vary considerably.
2. A device that maintains the terminal voltage of a generator or other voltage source within required limits despite variations in input voltage or load.
3. A circuit that includes a sensor capable of monitoring the load and restoring the output voltage to close tolerance limits despite changes in both the load and the input voltage.
4. Any electrical or electronic device that maintains the voltage of a power source within acceptable limits.

The voltage regulator is needed to keep voltages within the prescribed range that can be tolerated by the electrical equipment using that voltage.

Voltage regulators also are used in electronic equipment in which excessive variations in voltage would be detrimental.