race vs buck

race and buck both are nouns.

Word	Noun	Adjective	Verb	Adverb
race	Yes	No	Yes	No
buck	Yes	No	Yes	No

As verbs, buck is a hyponym of race; that is, buck is a word with a more specific, narrower meaning than race:

Other hyponyms of race include barge, push forward, thrust ahead, charge, shoot, shoot down, tear, dart, dash, flash, scoot, scud, shoot.

race (noun)	buck (noun)
a canal for a current of water	mature male of various mammals (especially deer or antelope)
a contest of speed	a framework for holding wood that is being sawed
any competition	a gymnastic horse without pommels and with one end elongated; used lengthwise for vaulting
people who are believed to belong to the same genetic stock	a piece of paper money worth one dollar
(biology) a taxonomic group that is a division of a species; usually arises as a consequence of geographical isolation within a species
the flow of air that is driven backwards by an aircraft propeller

race (verb)	buck (verb)
compete in a race	jump vertically, with legs stiff and back arched
move hurridly	move quickly and violently
cause to move fast or to rush or race	resist
to work as fast as possible towards a goal, sometimes in competition with others	to strive with determination