onomatopoeical vs echoic

onomatopoeical and echoic both are adjectives.

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

As adjectives, onomatopoeical and echoic are synonyms defined as:

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

Other synonyms of onomatopoeical include imitative, onomatopoeic, onomatopoetic.

onomatopoeical (adjective)	echoic (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