colloquialism

noun2

1. •
   A colloquial word or phrase; a common spoken expression.

   • Before embarking on her trip, Kaefer expected to find a pan-Antarctic vocabulary, but quickly discovered there were distinct colloquialisms within each station. — 2024
2. •
   A colloquial manner of speaking.

   • The differences between slang, colloquialism and jargon are not clear-cut. — 1996