( of a doctor, police officer, etc. ) available for work if necessary, especially in an emergency :
I'll be on call the night of the party.
( of a doctor, police officer, etc. ) available for work if necessary, especially in an emergency :
I'll be on call the night of the party.
Oxford Advanced Learner's English Dictionary. Оксфордский английский словарь для изучающик язык на продвинутом уровне. 2005