Wiktionary
stock phrase
n. (context idiomatic English) A phrase frequently or habitually used by a person or group, and thus associated with them.
Usage examples of "stock phrase".
Eddie had once told him that he didn't even dream in the Sun People language anymore, but now and then he used a stock phrase.
He sounded tolerably Japanese when he brought out the stock phrase.
That became a stock phrase with him and we were to hear it very often.