restrainer vs overcomer

restrainer and overcomer both are nouns.

Word	Noun	Adjective	Verb	Adverb
restrainer	Yes	No	No	No
overcomer	Yes	No	No	No

As nouns, overcomer is a hyponym of restrainer; that is, overcomer is a word with a more specific, narrower meaning than restrainer:

restrainer: a person who directs and restrains
overcomer: someone who overcomes and establishes ascendancy and control by force or persuasion

Other hyponyms of restrainer include nazi, subduer, surmounter, suppresser, suppressor, withholder.

restrainer (noun)	overcomer (noun)
a person who directs and restrains	someone who overcomes and establishes ascendancy and control by force or persuasion
a chemical that is added to a photographic developer in order to retard development and reduce the amount of fog on a film