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ac

/eɪˈsiː/

noun

Origin

English

alternating current / air conditioning — Initialism representing descriptive technical terms.

Overview

Meaning Now

  • an abbreviation for 'alternating current', an electric current that reverses its direction many times a second at regular intervals.
  • an abbreviation for 'air conditioning', a system used to cool and dehumidify the air in an enclosed space.

Language path

English

Earliest form

AC

Earliest period

late 19th century

Journey

The use of 'AC' became ubiquitous with the 'War of Currents' in the late 1880s, where alternating current (championed by Tesla and Westinghouse) competed with Thomas Edison's direct current (DC) for the standard of power distribution.

Evolution

  1. Late 19th Century

    alternating current

    “Electrical current type.”

    Coined to contrast with direct current (DC).

  2. Mid 20th Century

    air conditioning

    “Climate control system.”

    Popularized as standard consumer technology.

Connections

Word parts

a

other

First letter of initialism.

c

other

First letter of initialism.

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External references use DefinedTerm semantics.