It Support Vocabulary

noun a period of time during which a person or service is available to be contacted or called upon when needed

adjective describing a person or service that is available to be contacted or called upon when needed

preposition indicating that someone is available or ready to respond to a request or emergency

• The doctor is on call this weekend in case of any emergencies.
• I'll be on call for any questions you have about the project.
• I have to be on call for work tonight, so I can't go out with you guys.
• As a parent, you're always on call for your children, no matter what time of day it is.