Definitions for call in
a telephone call to a radio station or a television station in which the caller participates in the on-going program
summon to enter
"The nurse called in the next patient"
summon to a particular activity or employment
"Experts were called in"
visit, call in, call(verb)
pay a brief visit
"The mayor likes to call on some of the prominent citizens"
take a player out of a game in order to exchange for another player
make a phone call
"call in to a radio station"; "call in sick"
call, call in(verb)
demand payment of (a loan)
"Call a loan"
recall, call in, call back, withdraw(verb)
cause to be returned
"recall the defective auto tires"; "The manufacturer tried to call back the spoilt yoghurt"
Kernerman English Learner's Dictionary
to officially ask sb to help
They called in the FBI after the shooting.
to phone the place where you work
Jay called in to say he'd be late.
to phone a TV or radio station to speak on the air
listeners calling in to comment
To communicate with a base etc, by telephone.
To summon someone, especially for help or advice.
To withdraw something from sale or circulation.