24/7 or 24-7 or 24X7 (?tw?n ti?f?r ?s?v ?n, -?fo?r-, ?tw?n ti-) Slang. adv. 1. continually; constantly: They’re together 24/7. adj. 2. continual; constant: The manufacturer offers 24/7 customer support. Also, twen?ty-four` sev?en. [1985?90; shortening of twenty-four hours a day, seven days a week] Random House Kernerman Webster’s College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.