bongo drum vs bongo

bongo drum and bongo both are nouns.

Word	Noun	Adjective	Verb	Adverb
bongo drum	Yes	No	No	No
bongo	Yes	No	No	No

As nouns, bongo drum and bongo are synonyms defined as:

bongo drum (noun)	bongo (noun)
a small drum; played with the hands	large forest antelope of central Africa having a reddish-brown coat with white stripes and spiral horns
	a small drum; played with the hands