cetacean vs fluke

cetacean and fluke both are nouns.

Word	Noun	Adjective	Verb	Adverb
cetacean	Yes	Yes	No	No
fluke	Yes	No	No	No

cetacean (noun)	fluke (noun)
large aquatic carnivorous mammal with fin-like forelimbs no hind limbs, including: whales, dolphins, porpoises, narwhals	parasitic flatworms having external suckers for attaching to a host
	either of the two lobes of the tail of a cetacean
	flat bladelike projection on the arm of an anchor
	a barb on a harpoon or arrow
	a stroke of luck

cetacean (adjective)	fluke (adjective)
of or relating to whales and dolphins etc