number sign
B2Neutral to technical; the term 'hashtag' dominates in informal/social media contexts.
Definition
Meaning
The symbol #, used primarily to indicate a number or position in a sequence, and as a fundamental character in computing and telecommunications.
In contemporary usage, it is widely recognized as the 'hashtag' symbol on social media platforms for tagging topics. In music, it denotes a sharp note. In North America, it is commonly called the 'pound sign', especially on telephones.
Linguistics
Semantic Notes
The meaning is highly context-dependent: numeric (No. 1), telephonic (press #), computational (programming comment), social (metadata tag), or musical (pitch alteration).
Dialectal Variation
British vs American Usage
Differences
In the UK, 'hash' or 'hash sign' is common, especially for the telephone key. 'Number sign' is understood but less frequent in everyday speech. In the US, 'pound sign' (for weight or telephone) and 'number sign' are both used, with 'hashtag' now prevalent for its social media function.
Connotations
In British English, 'hash' is neutral and functional. In American English, 'pound sign' can cause minor ambiguity with the currency symbol £.
Frequency
'Hashtag' has largely supplanted both terms in global digital discourse. 'Number sign' remains standard in formal publishing and computing documentation.
Vocabulary
Collocations
Grammar
Valency Patterns
[verb] + the + number sign (e.g., enter, press, use, denote)the number sign + [verb] (e.g., indicates, precedes, follows)[noun] + with/without + a number signVocabulary
Synonyms
Strong
Neutral
Weak
Vocabulary
Antonyms
Phrases
Idioms & Phrases
- “to be number one with a bullet (music chart idiom, unrelated but uses #)”
- “under the hashtag (modern idiom for categorised online discussion)”
Usage
Context Usage
Business
Used in internal codes or product references (e.g., 'Please reference order #4567').
Academic
Rare; may appear in linguistics or music theory to denote the symbol itself.
Everyday
Mostly related to telephone instructions ('Press # to continue') or social media ('Add a hashtag to your post').
Technical
Ubiquitous in computing (e.g., comment in Perl, Python; hexadecimal escape in URLs; CSS id selector).
Examples
By Part of Speech
noun
British English
- The hash key is in the bottom right corner of the keypad.
- To reset, you must enter the code followed by the number sign.
American English
- The pound sign on your phone is also called a number sign.
- The tweet's visibility depended on a popular hashtag.
Examples
By CEFR Level
- The number sign looks like a small grid.
- My phone has a number sign button.
- In the address, flat number 5 is written with a number sign.
- To finish, press the star key and then the number sign.
- The developer used a number sign to comment out several lines of code.
- The campaign's hashtag, created from the number sign and a keyword, trended online.
- The octothorpe, or number sign, evolved from the Latin abbreviation 'lb' for libra pondo.
- Metadata protocols often utilise the number sign as a delimiter for specific queries.
Learning
Memory Aids
Mnemonic
Imagine a window with four panes (#) and a number taped to each pane - it's a 'number sign'.
Conceptual Metaphor
A GRID or CAGE for categorisation (hashtag traps a topic); a LADDER for ranking (No. 1).
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Direct translation 'знак номера' is understood but unnatural. The symbol is чаще called 'решетка' (grid/lattice) in IT/telephony contexts. 'Hashtag' is adopted as 'хэштег'. Avoid using 'номерной знак', which means license plate.
Common Mistakes
- Calling it a 'sharp' (#) in non-musical contexts, confusing it with the 'percent sign' (%), using 'hashtag' when referring to the symbol's function on a telephone keypad.
Practice
Quiz
In which context would the term 'octothorpe' most accurately be used?
FAQ
Frequently Asked Questions
The symbol (#) is the same. 'Hashtag' specifically refers to its use on social media as a metadata tag (e.g., #ThrowbackThursday). 'Number sign' is the generic name for the character.
This comes from its historical use as an abbreviation for 'pound weight' (lb.), where the superimposed 'lb' with a stroke through it eventually stylised into #.
You would typically say 'hash'. For example, 'Dial 020 and then 7946, followed by hash, 0583'.
Not traditionally. However, 'to hashtag' is a recognised verb meaning to add a hashtag to digital content.
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