a change, result, or consequence that happens because something else happens first
The medicine took effect within an hour and the pain eased.
New safety rules had a positive effect on the factory’s accident rate.
✦ From Latin effectus “accomplishment, result,” from efficere “to accomplish.”
the impression or feeling that something produces on a person
The lighting created a dramatic effect on the stage.
Her speech had a powerful effect on the audience, moving many to tears.
a visual or sound device used in films, theater, or recordings to create an imagined scene or atmosphere
The explosion effect in the movie looked incredibly real.
They added a rain effect on stage to make the scene more convincing.
to make something happen; to bring about or cause
The new CEO hopes to effect major changes in company culture.
The peace treaty finally effected an end to the decade-long conflict.
an additional and usually undesirable effect of a drug or medical treatment, in addition to the intended beneficial effect.
A common side effect of this antibiotic is an upset stomach.
She started having side effects like dizziness after the first dose.
✦ First recorded in the 1930s in pharmacology, combining 'side' (secondary, additional) and 'effect' (result, outcome).
in computing, any change in the system or observable state caused by execution of a program or function, other than its primary return value.
Updating a database inside a function creates a side effect.
Good code minimizes side effects for predictability.
✦ Adopted from medicine into computer science in the late 1960s, particularly in discussions of functional programming.
