hairdressing vs shampoo

hairdressing and shampoo both are nouns.

Word	Noun	Adjective	Verb	Adverb
hairdressing	Yes	No	No	No
shampoo	Yes	No	Yes	No

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

hairdressing: care for the hair: the activity of washing or cutting or curling or arranging the hair
shampoo: the act of washing your hair with shampoo

Other hyponyms of hairdressing include brush, brushing, comb, combing, hairweaving.

hairdressing (noun)	shampoo (noun)
care for the hair: the activity of washing or cutting or curling or arranging the hair	the act of washing your hair with shampoo
a toiletry for the hair	cleansing agent consisting of soaps or detergents used for washing the hair

hairdressing (verb)	shampoo (verb)
	use shampoo on (hair)