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.

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Example Sentences

See Examples For:

on call

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

After his mother died — a loss reflected in his fiction — he moved in with his now-wife and was on call to help with her funeral home.

From Los Angeles Times ● Apr. 16, 2026

The team of specialists is on call 24 hours a day to collect the most poorly children and babies and take them to intensive care, supporting 27 hospitals across the south of England.

From BBC ● Mar. 4, 2026

I thought it was an injury from Pilates, but, after a couple of weeks of the pain, I went to see the nurse practitioner on call at my doctor’s office.

From The Wall Street Journal ● Feb. 13, 2026

—Sir, Dr. Carrothers was the doctor on call tonight, but as I told you, he had a sudden emergency.

From "Tears of a Tiger" by Sharon M. Draper