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Synonyms

on call

Idioms  

  1. Available if summoned, as in Medical residents are required to be on call at least three nights a week. This expression originated as at call in the late 1500s. Also see at someone's beck and call.

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Having a good contractor on call is now a must-have for companies building power plants, and they are willing to pay up for them.

From Barron's • May 4, 2026

It has 40 volunteers who are on call 24/7, and who actively work with local people to prevent crime and increase safety by working with police and other agencies, according to its website.

From BBC • Apr. 29, 2026

New rules will mean reservists remain on call for an extra decade, and lower the threshold for them being called into service.

From BBC • Jan. 15, 2026

It wasn’t just the activists on call — block after block was ready.

From Los Angeles Times • Nov. 9, 2025

“They’re both on call all night,” he informs us.

From "Leah on the Offbeat" by Becky Albertalli

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.