usage vs activity

usage and activity both are nouns.

Word	Noun	Adjective	Verb	Adverb
usage	Yes	No	No	No
activity	Yes	No	No	No

As nouns, activity is a hypernym of usage; that is, activity is a word with a broader meaning than usage:

usage (noun)	activity (noun)
the act of using	any specific behavior
accepted or habitual practice	the trait of being active; moving or acting rapidly and energetically
the customary manner in which a language (or a form of a language) is spoken or written	an organic process that takes place in the body
	a process existing in or produced by nature (rather than by the intent of human beings)
	the state of being active
	(chemistry) the capacity of a substance to take part in a chemical reaction