tautology.

1. An expression that repeats an idea in different words without adding useful meaning.

2. A logical statement that is true under every relevant assignment of truth values.

Use it for

Words that belong together

• verbal tautology
• avoid tautology

On the page

The phrase “an identical copy of exactly the same thing” invited a charge of tautology.

She removed a verbal tautology from the conclusion.

Usage notes

Primary category: academic / formal. Forms: Singular tautology; plural tautologies. Legacy lexical fields mirror sense 1 only. Use numbered sense fields for all meanings.