change of mind vs turnabout

change of mind and turnabout both are nouns.

Word	Noun	Adjective	Verb	Adverb
change of mind	Yes	No	No	No
turnabout	Yes	No	No	No

As nouns, change of mind and turnabout are synonyms defined as:

Other synonyms of change of mind include flip-flop, reversal, turnaround.

change of mind (noun)	turnabout (noun)
a decision to reverse an earlier decision	turning in the opposite direction
	a decision to reverse an earlier decision