Middle English word turnen comes from Old French torner, Old English tyrnan, and later Old English turnian (To turn on a lathe.)

Detailed word origin of turnen

Dictionary entry	Language	Definition
torner	Old French (fro)	(transitive, or, intransitive) to turn. To return; to go back.
tyrnan	Old English (ang)
turnian	Old English (ang)	To turn on a lathe.
turnen	Middle English (enm)	To turn.

Words with the same origin as turnen