reverse vs turn back

reverse is a noun but turn back is not a noun.

Word	Noun	Adjective	Verb	Adverb
reverse	Yes	Yes	Yes	No
turn back	No	No	Yes	No

As verbs, turn back is a hyponym of reverse; that is, turn back is a word with a more specific, narrower meaning than reverse:

As verbs, reverse and turn back are synonyms defined as:

Other synonyms of reverse include invert.

reverse (noun)	turn back (noun)
(American football) a running play in which a back running in one direction hands the ball to a back running in the opposite direction
turning in the opposite direction
the gears by which the motion of a machine can be reversed
the side of a coin or medal that does not bear the principal design
an unfortunate happening that hinders or impedes; something that is thwarting or frustrating
a relation of direct opposition

reverse (adjective)	turn back (adjective)
of the transmission gear causing backward movement in a motor vehicle
directed or moving toward the rear
reversed (turned backward) in order or nature or effect

reverse (verb)	turn back (verb)
change to the contrary	go back to a previous state
turn inside out or upside down	turn inside out or upside down
reverse the position, order, relation, or condition of	hold back, as of a danger or an enemy; check the expansion or influence of
rule against	retrace one's course
cancel officially	force to go away; used both with concrete and metaphoric meanings