countercheck vs double check

countercheck and double check both are nouns.

Word	Noun	Adjective	Verb	Adverb
countercheck	Yes	No	Yes	No
double check	Yes	No	No	No

As nouns, countercheck and double check are synonyms defined as:

countercheck and double check: something that checks the correctness of a previous check

countercheck (noun)	double check (noun)
something that checks the correctness of a previous check	something that checks the correctness of a previous check
a check that restrains another check

countercheck (verb)	double check (verb)
check a second time
oppose or check by a counteraction