abuse vs ill-usage

abuse and ill-usage both are nouns.

Word	Noun	Adjective	Verb	Adverb
abuse	Yes	No	Yes	No
ill-usage	Yes	No	No	No

As nouns, abuse and ill-usage are synonyms defined as:

Other synonyms of abuse include ill-treatment, maltreatment.

abuse (noun)	ill-usage (noun)
improper or excessive use	cruel or inhumane treatment
cruel or inhumane treatment
a rude expression intended to offend or hurt

abuse (verb)	ill-usage (verb)
change the inherent purpose or function of something
use wrongly or improperly or excessively
use foul or abusive language towards
treat badly