turn of phrase
A particular arrangement of words, as in I'd never heard that turn of phrase before, or An idiom can be described as a turn of phrase. This idiom alludes to the turning or shaping of objects (as on a lathe), a usage dating from the late 1600s.
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.