# tilde

Pronunciation: say "TIL-duh" /ˈtɪldə/

## Noun

1. A written symbol ⟨~⟩, also called a swung dash or wave dash, and known to computer users as a squiggle or twiddle.
   - Simple: A wavy mark shaped like ~, used in writing, math, and computer text.
   - _Designers sometimes use a tilde as a decorative flourish between section titles._
   - _In the shell, a tilde stands in for your home directory._
2. A wavy diacritical mark ⟨˜⟩ placed over a letter to change the way the letter is pronounced.
   - Simple: A small wavy mark (˜) written above a letter to change how the letter is said.
   - _In phonetic transcription, a tilde above a vowel marks it as nasal._
   - _The typesetter's font had no tildes, so readers of the atlas mispronounced several place names._
3. A symbol placed before a quantity to indicate approximation, in both English prose and mathematics, as in '~30 pounds'.
   - Simple: A wavy mark used before a number to mean 'about' or 'roughly'.
   - _The report prefixed each figure with a tilde to flag rough estimates._
   - _In his notes he scribbled a tilde before the population count he wasn't sure of._
4. The character encoded as decimal 126 in the 1967 ASCII set and later carried into the Unicode standard.
   - Simple: The keyboard character ~ stored as the number 126 in a computer's character set.
   - _In ASCII, the tilde sits at decimal 126, near the end of the printable characters._
   - _Unicode kept the tilde at the same code point it held in ASCII._
5. A punctuation mark indicating a range from one number to another, a use common in Asia where the symbol is also called a wave dash.
   - Simple: A wavy mark used between two numbers to show a range, common in Asia.
   - _Japanese price tags use a tilde to show a range, as in '1000~2000 yen'._
   - _The schedule listed the festival dates with a tilde between the start and end._
6. In lexicography, the ⟨~⟩ symbol used to stand for a repetition of the entry word or item, in which use it is also called a swung dash.
   - Simple: In dictionaries, a wavy mark used to stand in for the word being explained.
   - _Under “break,” the entry lists “~ even” and “~ the ice,” each tilde standing for the headword itself._
   - _The style sheet for the new glossary tells editors to use a tilde, not a hyphen, for every repeated term._
7. An alternate form of the logical negation operator, usually written ¬, placed before a proposition to negate it.
   - Simple: In logic, a wavy mark put before a statement to mean 'not'.
   - _In propositional logic, a tilde before P denotes the negation of P._
   - _Some textbooks prefer a tilde to the ¬ symbol when writing negations._

## Other meanings

- (noun) Another name for the Vietnamese tone mark dấu ngã, which is placed above a vowel to indicate a creaky rising tone (thanh ngã).
- (noun) Another name for apex, a curved diacritic used in the 17th century to mark final nasalization in the early Vietnamese alphabet. It was an adoption of the Portuguese tilde.

## Origin

Borrowed from Spanish tilde, from Latin titulus ("superscript") or from tildar. It is a doublet of titer/titre, title, titlo, tittle, and titulus.

Source: DictionaryAI, https://dictionaryai.com/define/tilde (written from Wiktionary data, CC BY-SA 4.0: https://creativecommons.org/licenses/by-sa/4.0/).