air-conditioner

IPA/ˈeə kəndɪʃənə(r)/
IPA/ˈer kəndɪʃənər/

air-conditioner — noun

1. a machine that makes the inside of a room or building cooler and usually drier.

1.nounA2
Definition

a machine that makes the inside of a room or building cooler and usually drier.

Example

Please turn on the air-conditioner before the guests arrive.

collocation: turn on the air-conditioner

The air-conditioner in Room 302 stopped working during the meeting.

pattern: air-conditioner + in + place

Common collocations
  • turn on the air-conditioner
  • switch off the air-conditioner
  • set the air-conditioner to 26 degrees
  • air-conditioner remote
  • air-conditioner repair
Synonyms
  • AC

    informal short form, especially common in speech, signs, and repair ads

  • air conditioner

    the same noun written without a hyphen; this spelling is very common

  • air-conditioning system

    broader and more formal; can mean the whole built-in cooling system

  • cooling unit

    more technical; often used by sellers or repair workers

Antonyms
  • heater

    a machine used to warm a room instead of cooling it

Grammar Patterns

turn on the air-conditioner

set the air-conditioner to + temperature

Usage Note

Often used with verbs such as turn on, switch off, set, fix, and install. The spelling without the hyphen, 'air conditioner', is also very common, and many speakers shorten it to 'AC' in everyday use.

Common Mistakes

Please open the air-conditioner.
Please turn on the air-conditioner.
for machines, use 'turn on' or 'switch on', not 'open'.
The shop has air-conditioner.
The shop has an air-conditioner.
as a singular countable noun, it needs an article.

Word family

Synonym discussion

Sense: noun/1

'Air-conditioner' is the everyday name for a machine that cools indoor air. 'Air conditioner' is simply the more common unhyphenated spelling of the same word. 'AC' is the short informal form, especially common in speech, shop signs, and repair notices. 'Air-conditioning system' is broader and more formal: it can mean the whole built-in system in a house, office, hotel, or car, not only one machine on the wall or in the window. 'Cooling unit' also sounds more technical and is often used in product descriptions or by repair workers. Compare: 'The bedroom air-conditioner is broken,' 'Call the AC repair shop,' and 'The hotel installed a new air-conditioning system.'

air-conditioner ↗AC ↗air conditionerair-conditioning systemcooling unit

Common collocations

Nouns

  • air-conditioner remote
  • air-conditioner filter
  • air-conditioner repair
  • window air-conditioner

Phrases

  • turn on the air-conditioner
  • switch off the air-conditioner
  • install an air-conditioner
  • set the air-conditioner to 26 degrees

Prepositions

  • under the air-conditioner
  • without an air-conditioner

Etymology

LatinFrenchEnglish

This compound was formed in English in the early 20th century from 'air' and 'conditioner'. It appeared after 'air conditioning' became the name for controlling indoor temperature and moisture. The second part comes from 'condition', a word that reached English through French from Latin. So an air-conditioner is, literally, a machine that puts the air into a chosen condition.

First known use

1908

1908, in the meaning defined above