bit vs check bit

bit and check bit both are nouns.

Word	Noun	Adjective	Verb	Adverb
bit	Yes	No	No	No
check bit	Yes	No	No	No

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

bit: a unit of measurement of information (from binary + digit); the amount of information in a system having two equiprobable states
check bit: (computer science) a bit that is used in an error detection procedure in which a 0 or 1 is added to each group of bits so that it will have either an odd number of 1's or an even number of 1's; e.g., if the parity is odd then any group of bits that arrives with an even number of 1's must contain an error

Other hyponyms of bit include parity, parity bit.

bit (noun)	check bit (noun)
the cutting part of a drill; usually pointed and threaded and is replaceable in a brace or bitstock or drill press	(computer science) a bit that is used in an error detection procedure in which a 0 or 1 is added to each group of bits so that it will have either an odd number of 1's or an even number of 1's; e.g., if the parity is odd then any group of bits that arrives with an even number of 1's must contain an error
piece of metal held in horse's mouth by reins and used to control the horse while riding
the part of a key that enters a lock and lifts the tumblers
a short performance that is part of a longer program
a small fragment
an instance of some kind
a small amount of solid food; a mouthful
a small fragment of something broken off from the whole
a unit of measurement of information (from binary + digit); the amount of information in a system having two equiprobable states
a small piece or quantity of something
an indefinitely short time