Word Usage: Affect and Effect

Just what is the difference between affect and effect? These two words are homonyms—words that sound alike but have different meanings. In this case, only one letter sets them apart.

To add to the confusion, both words can function as a noun or a verb. Knowing when to use each in a particular sentence can be a challenge.

Let's take a closer look at them in this word usage tip.

Examples

Affect is most commonly used as a verb and effect is most commonly used as a noun.

Example
Drug A affected symptom severity.

Example
Drug B has no effect on glucose levels.

Sometimes, however, affect is used as a noun and effect as a verb. These uses are far less common than those described above.

Example
The participant showed an unusual affect in response to the photo.

Example
The treatment effected a change in lung function.

Quick Tips: Affect vs Effect

Try the following memory aid for affect as a verb and effect as a noun: