Word Confusion: Affect versus Effect

Plural for the noun and third person present verb: affects
Past tense or past participle: affected
Gerund or present participle: affecting

Plural for the noun and third person present verb: effects
Past tense or past participle: effected
Gerund or present participle: effecting

When speaking about psychology with reference to someone’s mood.

(Psychologists know that you can never really understand what someone else is feeling. You can only know how they appear to be feeling.)

Be warned that affect as a noun is almost entirely restricted to psychology.

Verb, transitive:
To influence ²

To act in a way that you don’t feel

Have an effect on

Make a difference to

• Touch the feelings of someone
• Move emotionally

Pretend to have or feel something ³

• Use, wear, or assume something pretentiously or so as to make an impression on others

• The state of being or becoming operative
• The extent to which something succeeds or is operative
• [Physics; with modifier] A physical phenomenon, typically named after its discoverer
• An impression produced in the mind of a person

[Effects] The lighting, sound, or scenery used in a play, movie, or broadcast

Verb, transitive:
To bring about, accomplish

Cause something to happen

Verb, transitive:
The arrows affected the aardvark.

The rain affected Amy’s hairdo.

She affected an air of superiority.

The dampness began to affect my health.

Your attitude will affect how successful you are.

The atrocities he witnessed have affected him most deeply.

As usual I affected a supreme unconcern.

A book that affects to loathe the modern world.

He was an American who had affected a British accent.

The sound effects were amazing.

Her face shows the lethal effects of hard drugs.

Politicians really do have some effect on the lives of ordinary people.

Wind power can be used to great effect.

The Doppler effect is when something sounds louder as it approaches you and sounds fainter as it goes away.

Gentle music can have a soothing effect.

The production relied too much on spectacular effects.

Thank god our insurance covers personal effects.

Verb, transitive:
The rain had no effect on Amy’s hairdo.

Nature always effected a cure.

Budget cuts were quietly effected over four years.

1. Late 19th century and coined in German from the Latin affectus meaning disposition, from afficere meaning to influence. See also ³.
2. Late Middle English in the sense of attack as a disease, from the French affecter or the Latin affect- meaning influenced or affected from the verb afficere. See also ³.
3. Late Middle English from the French affecter or the Latin affectare meaning aim at and a frequentative of afficere meaning work on or influence from ad- (at, to) + facere (do).

   The original sense was like or love, hence (like to) use, assume, etc.