combing vs hairdressing

combing and hairdressing both are nouns.

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

As nouns, hairdressing is a hypernym of combing; that is, hairdressing is a word with a broader meaning than combing:

combing: the act of drawing a comb through hair
hairdressing: care for the hair: the activity of washing or cutting or curling or arranging the hair

Other hypernyms of combing include hair care, haircare.

combing (noun)	hairdressing (noun)
the act of drawing a comb through hair	care for the hair: the activity of washing or cutting or curling or arranging the hair
	a toiletry for the hair