hair vs whisker

hair and whisker both are nouns.

Word	Noun	Adjective	Verb	Adverb
hair	Yes	No	No	No
whisker	Yes	No	Yes	No

As nouns, whisker is a hyponym of hair; that is, whisker is a word with a more specific, narrower meaning than hair:

hair: a filamentous projection or process on an organism
whisker: a long stiff hair growing from the snout or brow of most mammals as e.g. a cat

Other hyponyms of hair include bristle, sensory hair, vibrissa, seta, pilus.

As nouns, hair and whisker are synonyms defined as:

Other synonyms of hair include hair's-breadth, hairsbreadth.

hair (noun)	whisker (noun)
a filamentous projection or process on an organism	a long stiff hair growing from the snout or brow of most mammals as e.g. a cat
cloth woven from horsehair or camelhair; used for upholstery or stiffening in garments	a very small distance or space
a covering for the body (or parts of it) consisting of a dense growth of threadlike structures (as on the human head); helps to prevent heat loss
any of the cylindrical filaments characteristically growing from the epidermis of a mammal
filamentous hairlike growth on a plant
a very small distance or space

hair (verb)	whisker (verb)
	furnish with whiskers