Set phrase

A set phrase (also known as, a phraseme or fixed phrase) is a phrase which parts are fixed in a certain order, even if the phrase could be changed without harming the literal meaning. This is because a set phrase is a culturally accepted phrase. A set phrase does not necessarily have any literal meaning in and of itself. Set phrases may function as idioms (e.g. "red herring") or as words with a unique referent (e.g. "Red Sea"). There is no clear dividing line between a commonly used phrase and a set phrase. It is also not easy to draw a clear distinction between set phrases and compound words.
It is different from a proverb in that it is used as a part of a sentence, and is the standard way of expressing a concept or idea.
In theoretical linguistics, two-word set phrases are said to arise during the generative formation of English nouns.
A certain stricter notion of set phrases, more in line with the concept of a lexical item, provides an important underpinning for the formulation of meaning–text theory.
In other languages.
Fixed expressions occur in other languages, as well, such as: