Phrases & IdiomsPhrase guide

Necessary Evil

“necessary evil” is something unpleasant or undesirable that people accept because it is considered necessary for a particular result.

Quick answer

A “necessary evil” is something unpleasant or undesirable that people accept because it is considered necessary for a particular result.

Key details

Canonical Formnecessary evil
Core Meaningsomething unpleasant that is accepted because it is needed to achieve a result

Further guidance

History Boundary

Current dictionary-supported meaning is published without claiming an exact inventor, coinage date, or absolute first use.

Meaning

something unpleasant that is accepted because it is needed to achieve a result

Usage Boundary

The phrase expresses reluctant acceptance: calling something a necessary evil does not mean it is good, only that the speaker sees it as needed for an outcome.

Sources and evidence

Sources are shown with the role they play in this guide. Historical or style-sensitive claims are kept within the evidence boundary described above.

  1. Necessary evil — Cambridge Dictionary (opens in a new tab)Cambridge Dictionary · Current meaning of necessary evil

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