crawler vs worker

crawler and worker both are nouns.

Word	Noun	Adjective	Verb	Adverb
crawler	Yes	No	No	No
worker	Yes	No	No	No

As nouns, worker is a hypernym of crawler; that is, worker is a word with a broader meaning than crawler:

Other hypernyms of crawler include actor, doer.

crawler (noun)	worker (noun)
terrestrial worm that burrows into and helps aerate soil; often surfaces when the ground is cool or wet; used as bait by anglers	sterile member of a colony of social insects that forages for food and cares for the larvae
a person who tries to please someone in order to gain a personal advantage	a person who works at a specific occupation
a person who crawls or creeps along the ground	a member of the working class (not necessarily employed)
	a person who acts and gets things done