Adverse or Averse?

by Craig Shrives

What Is the Difference between "Adverse" and "Averse"?

"Adverse" means "harmful" or "hostile" (e.g., "adverse effect from the medicine.") "Averse" applies to people and means "against" or "unwilling to." "Averse" is used with "to" (e.g., "averse to hard work").

Even though their meanings are different, "adverse" and "averse" are easy to confuse because they sound so similar.

Quick Test on "Adverse" and "Averse"

It's your go. Select the correct one:
adverse averse

Using "Adverse"

"Adverse" means "harmful" or "hostile". For example:
  • I cannot operate in such adverse conditions. correct tick

Using "Averse"

"Averse" is used with "to." It means "against" or "unwilling to." For example:
  • Sarah has always been averse to smoking. correct tick
  • (Note that "averse" is used with "to.")

Top Tip

The word "averse" is used with "to," but "adverse" is not. So, if you've used the word "to," you need "averse" not "adverse."

More about "Adverse"

The adjective "adverse" means antagonistic, opposing, harmful, hostile, or unfavorable small American flag (unfavourable small British flag).

  • Adverse conditions including rain, snow, ice and fog affect your visibility. correct tick
  • He is not responsible for the adverse events in your life. correct tick

More about "Averse"

"Averse" is used with "to." It means against, strongly disinclined to, unwilling to, or loath to. (Most often, it refers to people.)

  • Are you averse to hunting? correct tick
  • The company staff are averse to change. correct tick

Synonyms of "Adverse"

The most commonly used synonyms for "adverse" are hostile, unfavourable, and harmful. Here are some examples of "adverse" aligned to those synonyms in sentences:
  • Hostile. They endured adverse weather conditions.
  • Unfavorable. Your decision will have an adverse impact.
  • Harmful. Strong coffee has an adverse effect on me.

Synonyms of "Averse"

Three common synonyms of "averse" are disinclined, unwilling, and loath. These carry different strengths of negativity. Here are some examples in sentences:
  • Disinclined. I am averse to swimming in the bay.
  • (Averse is not always a strong idea. It can imply hesitancy due to uncertainty.)
  • Unwilling. She is averse to meeting you again.
  • (Averse can imply a reluctance.)
  • Loath. I am averse to working with that clown.
  • (Averse can imply repugnance.)

A Video Summary

Here is a 2-minute video summarizing the difference between "adverse" and "averse."

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