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Definition of octothorpe

octothorpe

/ˈɑːk.tə.θɔːrp/
oc · to · thorpe
Plural:octothorpes
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octothorpe Lexical Profile

octothorpe Game Scores & Validity

• noun

1

The typographical symbol '#', traditionally used to represent the word 'number' or 'pound', and prominent on telephone keypads and in digital tagging.

Example

"The automated voice prompt instructed the caller to enter their account number followed by the octothorpe."

Synonyms
View all synonyms for octothorpe

Word Nuance & Usage

While 'octothorpe' is the official term coined for the symbol on telephone keypads, it is almost exclusively referred to as a 'hash', 'pound sign', or 'hashtag' in modern everyday speech.

• Rhymes for octothorpe

• Nearby Words

octogenarian
octopus
octoroon
octothorpe
octuplet
ocular
odd

Word Origin & Etymology

Coined in the 1960s by engineers at Bell Laboratories when adding the '#' symbol to Touch-Tone telephone keypads. 'Octo-' refers to the symbol's eight points, and 'thorpe' is commonly believed to be a tribute to American Olympic athlete Jim Thorpe.

Usage Trend

Historical frequency of usage in published text.

180019102020
Data source: Google Books Ngram Viewer

Cite this Entry

Wordmom. (2026). Definition of Octothorpe. In Wordmom Dictionary. Retrieved Nov 5, 2026, from https://wordmom.com/dictionary/octothorpe
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