echoic vs onomatopoeic

echoic and onomatopoeic both are adjectives.

Word	Noun	Adjective	Verb	Adverb
echoic	No	Yes	No	No
onomatopoeic	No	Yes	No	No

As adjectives, echoic and onomatopoeic are synonyms defined as:

echoic and onomatopoeic: (of words) formed in imitation of a natural sound

Other synonyms of echoic include imitative, onomatopoeical, onomatopoetic.

echoic (adjective)	onomatopoeic (adjective)
(of words) formed in imitation of a natural sound	(of words) formed in imitation of a natural sound
like or characteristic of an echo	of or relating to or characterized by onomatopoeia