Adverse

Synonyms:
1. hostile, inimical, unfriendly. 2. unfavorable; unlucky, unfortunate; disastrous, calamitous, catastrophic. See contrary.

Antonyms:
1–3. favorable.

Usage note:
The adjectives adverse and averse are related both etymologically and semantically, each having “opposition” as a central sense. Adverse is seldom used of people but rather of effects or events, and it usually conveys a sense of hostility or harmfulness: adverse reviews; adverse winds; adverse trends in the economy. Related nouns are adversity and adversary: Adversities breed bitterness. His adversaries countered his every move. Averse is used of persons and means “feeling opposed or disinclined”; it often occurs idiomatically with a preceding negative to convey the opposite meaning “willing or agreeable,” and is not interchangeable with adverse in these contexts: We are not averse to holding another meeting. The related noun is aversion: She has a strong aversion to violence. Averse is usually followed by to, in older use occasionally by from.