tiger vs worker

tiger and worker both are nouns.

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

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

Other hypernyms of tiger include actor, doer.

tiger (noun)	worker (noun)
large feline of forests in most of Asia having a tawny coat with black stripes; endangered	sterile member of a colony of social insects that forages for food and cares for the larvae
a fierce or audacious person	a person who works at a specific occupation
	a member of the working class (not necessarily employed)
	a person who acts and gets things done