Averse means (1) to be opposed or (2) to be strongly disinclined. Adverse means to be acting in opposition. Averse describes an attitude or a feeling, while adverse describes something that works against something else. The two adjectives are often confused.
Adverse‘s corresponding noun is adversity. Averse‘s is averseness (aversity is not a dictionary-recognized word). As adverbs, they’re inflected similarly—adversely and aversely.
Synonyms and examples
Averse—some of whose synonyms are opposed, reluctant, hostile, and disinclined—is most commonly used in reference to a person or a group of people—for example:
The yen jumped in Asian trade as investors became more averse to risk . . . [Reuters]
If you’re averse to spoilers, close your browser window right now. [Latino Review]
Averse is often used in the phrasal adjective risk-averse—frequently in financial contexts.
Adverse—some of whose synonyms are harmful, negative, unfavorable, and detrimental—usually refers to things, conditions, or actions—for example:
The panel concluded that sounds or vibrations emitted from wind turbines have no adverse effect on human health. [Simcoe Reformer]
But a study finds that having some adverse experiences in the past may make you mentally tougher. [Los Angeles Times]
