Question

Can you please explain to be what a idioms is?

Answer 1

a group of words established by usage as having a meaning not deducible from those of the individual words
synonyms:language, mode of expression, turn of phrase, style, speech, locution, diction, usage, phraseology, phrasing, phrase, vocabulary, terminology, parlance, jargon, argot, cant, patter, tongue, vernacula

Answer 2

Idioms are "a group of words used to have a meaning that cannot be expressed by individual words"

hope this helps