24/7

[Barnhart]

The term 24-7 is found in the Barnhart Dictionary Companion (Vol. 8.4,
1993).  It probably needs an updated treatment.

No origin was speculated at the time.  My guess is that it arose in the
slang/jargon of Silicon Valley.

Regards,
David

David K. Barnhart, Editor
The Barnhart Dictionary Companion [quarterly]
barnhart at highlands.com
www.highlands.com/Lexik

"Necessity obliges us to neologize."
Thomas Jefferson-August 16, 1813