nightcrawler vs earthworm

nightcrawler and earthworm both are nouns.

Word	Noun	Adjective	Verb	Adverb
nightcrawler	Yes	No	No	No
earthworm	Yes	No	No	No

As nouns, nightcrawler and earthworm are synonyms defined as:

nightcrawler and earthworm: terrestrial worm that burrows into and helps aerate soil; often surfaces when the ground is cool or wet; used as bait by anglers

Other synonyms of nightcrawler include angleworm, crawler, dew worm, fishing worm, fishworm, nightwalker, red worm, wiggler.

nightcrawler (noun)	earthworm (noun)
terrestrial worm that burrows into and helps aerate soil; often surfaces when the ground is cool or wet; used as bait by anglers	terrestrial worm that burrows into and helps aerate soil; often surfaces when the ground is cool or wet; used as bait by anglers