negative effect

/ˈnɛɡətɪv ɪˈfɛkt/ · neg.a.tive ef.fect

noun

A consequence or outcome that is undesirable or unfavorable. The negative effect of pollution on the environment has been well-documented.
A feeling or attitude that is pessimistic or unfavorable. The negative effect of the news on the stock market was immediate.

verb

To have an undesirable or unfavorable impact on something or someone. The new policy will negatively effect the company's bottom line.

Synonyms

adverse effect unfavorable outcome undesirable consequence negative impact pessimistic attitude unfavorable influence

Antonyms

positive effect favorable outcome desirable consequence positive impact optimistic attitude favorable influence

Did you know? The phrase 'negative effect' is often used in scientific and technical contexts to describe the unintended consequences of a particular action or policy.

Related terms

effect impact outcome consequence result outcome

Written by Lexi Wordsworth, Dictionary Editor 0 lookups Added Aug 11, 2026