Meaning of the word "be on call" in English

What does "be on call" mean in English? Explore the meaning, pronunciation, and specific usage of this word with Lingoland.

be on call

US /bi ɑn kɔl/
UK /bi ɒn kɔːl/

Idiom

to be available to work if needed, especially outside normal working hours

Example:
Doctors often have to be on call during weekends.
I can't go out tonight, I have to be on call for work.