idiom

UK: /ˈɪdiəm/ US: /ˈɪdiəm/ ,(id′ē əm)

WordReference Random House Learner's Dictionary of American English © 2025

id•i•om /ˈɪdiəm/   n. [countable]

1. Linguistics an expression or phrase that does not follow regular rules of grammar, or one whose meaning cannot be predicted from the meaning of its individual parts:
   The expression
   kick the bucket,
   meaning "to die,'' is an idiom in English.
2. Linguistics a language, dialect, or style of speaking typical of a person or of a group:
   the idiom of the arts folk.

WordReference Random House Unabridged Dictionary of American English © 2025

id•i•om  (id′ē əm), n. 

1. Linguistics an expression whose meaning is not predictable from the usual meanings of its constituent elements, as kick the bucket or hang one's head, or from the general grammatical rules of a language, as the table round for the round table, and that is not a constituent of a larger expression of like characteristics.
2. Linguistics a language, dialect, or style of speaking peculiar to a people.
3. Linguistics a construction or expression of one language whose parts correspond to elements in another language but whose total structure or meaning is not matched in the same way in the second language.
4. Linguistics the peculiar character or genius of a language.
5. a distinct style or character, in music, art, etc.:
   the idiom of Bach.

• Greek idíōma peculiarity, specific property equivalent. to idiō- (variant stem of idioûsthai to make one's own, appropriate, verb, verbal derivative of idiós; see idio-) + -ma noun, nominal suffix of result
• Latin idiōma
• 1565–75

Synonyms

• 1. See phrase. 

Collins Concise English Dictionary © HarperCollins Publishers::

idiom / ˈɪdɪəm/ noun

1. a group of words whose meaning cannot be predicted from the meanings of the constituent words, as for example (It was raining) cats and dogs
2. linguistic usage that is grammatical and natural to native speakers of a language
3. the characteristic artistic style of an individual, school, period, etc

Etymology: 16th Century: from Latin idiōma peculiarity of language, from Greek; see idio-

idiomatic / ˌɪdɪəˈmætɪk/, ˌidioˈmatical adjective

ˌidioˈmatically adverb