{{Punctuation marks|≡|caption=Identical to<!--
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{{about|the symbol|the horse jump|Oxer}}
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The triple bar, [[≡ (disambiguation)|]], is a symbol with multiple, context-dependent meanings. It has the appearance of a "[[Equals sign|=]]" sign with a third line.
In [[logic]], it has a similar meaning to the [[if and only if]] connective, ⇔. However, in some texts ⇔ is used as a symbol in logic formulas, while ≡ is for reasoning about those formulas (as in [[metalogic]]).
In mathematics it sometimes used a symbol for (although not the only one). Particularly, in number theory, it has the meaning of [[modular arithmetic|modular congruence]]: <math>a \equiv b \pmod N</math> if N divides a − b.
This symbol is also used when it appears in an equation which is a definition of its [[left-hand side]], that is an equation which is not derived but instead defined.
It is also used for "identical equality" of functions; one writes <math>f \equiv g</math> for two functions f, g if we have <math>f(x) = g(x)</math> for all x.
In [[chemistry]], the triple bar can be used to represent a [[triple bond]] between atoms. For example, HC≡CH is a common shorthand for [[acetylene]].
The triple bar character in [[Unicode]] as codepoint {{unichar|2261|IDENTICAL TO|html=}}. [[LaTeX]] \equiv corresponds to the triple bar.
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[[Category:Mathematical symbols]]
[[Category:Logic symbols]]
