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wait up

British  

verb

  1. to delay going to bed in order to await some event

  2. informal to halt and pause in order that another person may catch up

"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
wait up Idioms  

  1. Postpone going to bed in anticipation of someone or something, as in My parents always wait up until I get home, no matter how late it is . [Mid-1800s]

  2. Stop or pause so that another can catch up, as in Let's wait up for the stragglers , or Don't walk so fast; wait up for me . [ Colloquial ]

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.