IPA: /ˈɪdiəm/
KK: /ˈɪdiəm/
A phrase or expression in a language that has a meaning not easily understood from the individual words, often unique to a particular group or culture.
The phrase 'kick the bucket' is an idiom that means to die.
Idiom is derived from the Greek word "idioma" (meaning a peculiar phrase or expression) and the suffix "-ism" (indicating a characteristic or quality). The word "idiom" refers to a phrase or expression that has a figurative meaning distinct from its literal meaning, often specific to a particular language or group.
Think of a 'peculiar expression' ('idioma') that has a unique meaning in a language — that's what an idiom is.