caller

noun6

1. •
   The person who makes a telephone call.

   • ―I’ve got someone on the line. ―Who’s the caller?
2. •
   A visitor.
3. •
   The person who stands at the front of the hall and announces the numbers.
4. •
   The person who directs dancers in certain dances, such as American line dances and square dances.
5. •
   A function that calls another (the callee).

   • If the called function throws an exception, the caller should be prepared to handle the error.
6. •
   A whistle or similar item used to call foxes.