The triple bar, or tribar ≡, is a symbol with multiple, context-dependent meanings. It has the appearance of an equals sign ⟨=⟩ sign with a third line.

In mathematics, the triple bar is sometimes used as a symbol of identity or an equivalence relation.

Particularly, in geometry, it may be used either to show that two figures are congruent or that they are identical. In number theory, it has been used beginning with Carl Friedrich Gauss (who first used it with this meaning in 1801) to mean modular congruence.

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