examiner vs checker

examiner and checker both are nouns.

Word	Noun	Adjective	Verb	Adverb
examiner	Yes	No	No	No
checker	Yes	No	Yes	No

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

Other hyponyms of examiner include bank examiner, scrutiniser, scrutinizer, canvasser, scrutineer.

examiner (noun)	checker (noun)
an investigator who observes carefully	one of the flat round pieces used in playing the game of checkers
someone who administers a test to determine your qualifications	one who checks the correctness of something
	an attendant who checks coats or baggage

examiner (verb)	checker (verb)
	variegate with different colors, shades, or patterns
	mark into squares or draw squares on; draw crossed lines on