admission fee vs fee

admission fee and fee both are nouns.

Word	Noun	Adjective	Verb	Adverb
admission fee	Yes	No	No	No
fee	Yes	No	Yes	No

As nouns, fee is a hypernym of admission fee; that is, fee is a word with a broader meaning than admission fee:

admission fee (noun)	fee (noun)
the fee charged for admission	a fixed charge for a privilege or for professional services
	an interest in land capable of being inherited

admission fee (verb)	fee (verb)
	give a tip or gratuity to in return for a service, beyond the compensation agreed on