Unsupported titles/Number sign

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Character #
Unicode name NUMBER SIGN
Code point U+0023
Unicode block Basic Latin
" [U+0022] [U+0024] $



# (English symbol name number sign or hash or pound sign or octothorpe)

  1. (set theory) The cardinality of a set.
    #{ 5, 3, 7, 11 } = 4
  2. (computing) The hash character
  3. (mathematics, computer science) concatenation
  4. alternative form of
  5. (chess notation) checkmate
  6. (television) Used in subtitles to indicate that the enclosed text is song lyrics
  7. (Usenet) Used to pad the left side of a quotation from a manual or official source.
  8. (cartography) Used to denote a village.
  9. (syntax) Used to indicate that a sentence is grammatical but semantically strange.
  10. (phonology) Used to indicate a word boundary.


Derived terms[edit]

  • (small form variant)

Coordinate terms[edit]

  • (to pad a quotation on Usenet): > (for a quotation not necessarily from a manual or official source)

Usage notes[edit]


  • (chess): ++



The symbol # derives from the abbreviation lb for Latin libra (pound), via the medieval convention of indicating abbreviations with a bar, .


# (plural # or #s)

  1. (food packaging, US) Pound (unit of weight)
    3# — "three pounds"
  2. (followed by a numeral: used attributively) Number
    #3 — "number three"

Related terms[edit]


  • (number): no.

See also[edit]