high hat vs high-hat cymbal

high hat and high-hat cymbal both are nouns.

Word	Noun	Adjective	Verb	Adverb
high hat	Yes	No	No	No
high-hat cymbal	Yes	No	No	No

As nouns, high hat and high-hat cymbal are synonyms defined as:

high hat (noun)	high-hat cymbal (noun)
cymbals that are operated by a foot pedal	cymbals that are operated by a foot pedal
a man's hat with a tall crown; usually covered with silk or with beaver fur