usage vs custom

usage and custom both are nouns.

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

As nouns, usage and custom are synonyms defined as:

Other synonyms of usage include usance.

usage (noun)	custom (noun)
the act of using	accepted or habitual practice
accepted or habitual practice	habitual patronage
the customary manner in which a language (or a form of a language) is spoken or written	a specific practice of long standing
	money collected under a tariff

usage (adjective)	custom (adjective)
	made according to the specifications of an individual