overturn vs turn over

overturn is a noun but turn over is not a noun.

Word	Noun	Adjective	Verb	Adverb
overturn	Yes	No	Yes	No
turn over	No	No	Yes	No

As verbs, overturn and turn over are synonyms defined as:

Other synonyms of overturn include tip over, tump over.

As verbs, overturn and turn over are synonyms defined as:

overturn and turn over: cause to overturn from an upright or normal position

Other synonyms of overturn include bowl over, knock over, tip over, tump over, upset.

overturn (noun)	turn over (noun)
the act of upsetting something
an improbable and unexpected victory

overturn (verb)	turn over (verb)
change radically	think about carefully; weigh
rule against	turn up, loosen, or remove earth
cancel officially	turn upside down, or throw so as to reverse
turn from an upright or normal position	turn from an upright or normal position
cause to overturn from an upright or normal position	cause to overturn from an upright or normal position
cause the downfall of; of rulers	move by turning over or rotating
	cause to move around a center so as to show another side of
	place into the hands or custody of
	do business worth a certain amount of money