tilde (~)
Definition -
(1) In early printing it was placed above a letter to indicate that a following n or m was missing.
(2) In Spanish it is placed above the letter n to indicate a palatalized sound, as in señor.
(3) In mathematics it is used to show negation (e.g. something that is ~FALSE is TRUE).

Etymology -
The name was coined by a metathesis of the Catalan word title, which in turn derives from the Latin titulus, a title or a superscript.

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