bribe vs kickback

bribe and kickback both are nouns.

Word	Noun	Adjective	Verb	Adverb
bribe	Yes	No	Yes	No
kickback	Yes	No	No	No

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

bribe: payment made to a person in a position of trust to corrupt his judgment
kickback: a commercial bribe paid by a seller to a purchasing agent in order to induce the agent to enter into the transaction

Other hyponyms of bribe include hush money, payola, soap.

bribe (noun)	kickback (noun)
payment made to a person in a position of trust to corrupt his judgment	a commercial bribe paid by a seller to a purchasing agent in order to induce the agent to enter into the transaction

bribe (verb)	kickback (verb)
make illegal payments to in exchange for favors or influence