bong vs echo

bong and echo both are nouns.

Word	Noun	Adjective	Verb	Adverb
bong	Yes	No	Yes	No
echo	Yes	No	Yes	No

As verbs, echo is a hypernym of bong; that is, echo is a word with a broader meaning than bong:

Other hypernyms of bong include resound, reverberate, ring.

bong (noun)	echo (noun)
a dull resonant sound as of a bell	an imitation or repetition
	the repetition of a sound resulting from reflection of the sound waves
	a reflected television or radio or radar beam
	a close parallel of a feeling, idea, style, etc.
	a reply that repeats what has just been said