Word of the day · 18 July 2026
affect
/əˈfɛkt/
verb
To influence or produce a change in something or someone.
In a sentence
- Humidity can affect how paint dries on an exterior wall.
- The delay did not affect their decision to stay.
- How you frame a question can affect the answers you get.
In an image
Origin
From Latin affectare (to strive after, influence), related to afficere (to do something to, act upon).
History
Writers look this up because affect and effect sound alike and share a root, yet they do different jobs. As a verb, affect means to influence: weather can affect crops, news can affect a mood. Psychology also uses affect as a noun for felt emotion, which is why the word feels slippery in school essays. Keep the everyday verb sense first, then treat the noun as a specialist use.
Nearby words
influence · alter · effect
The verb people mix with effect: to act on a thing, not the result itself.