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24/7

or 24‐7, 24×7, twen·ty-four sev·en

[twen-tee-fawr sev-uh n, ‐fohr‐, twuhn-tee‐]Slang.
adverb
  1. continually; constantly: They're together 24/7.
adjective
  1. continual; constant: The manufacturer offers 24/7 customer support.

Origin of 24/7

1985–90; shortening of twenty-four hours a day, seven days a week
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for twenty-four-seven

twenty-four-seven

24/7

adverb
  1. informal twenty-four hours a day, seven days a week; constantly; all the timeconsultants would not be available 24/7
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
twenty-four-seven in Culture

24/7

Twenty-four hours a day, seven days a week: “This convenience store is open 24/7.” The term, which also appears as “24-7,” can be used figuratively to mean “with great time and effort”: “We worked on the design 24/7 in order to complete the work on time.” This phrase was coined in the late twentieth century.

The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.