handler

Noun

1. One who handles something (especially manually) or someone.
   • The handler of a weapon gets a symbolic sensation of deadly power.
   • Although the airline told them it took such action because they might spread the disease in their capacity as food handlers, neither was offered a transfer to other departments. - 1984 December 8, Christine Guilfoy,...
2. A controller, trainer, someone who handles a specified thing, animal or person (especially a prizefighter).
   • The spy's handler told him to approach the subject by posing as a dog handler.
   • They are also very sympathetic, especially Caesar’s orangutan advisor, Maurice (Karin Konoval), who takes a shine to a human moppet (Amiah Miller) he finds hiding in the back of a shack, and the poignant Bad Ape (a...
3. An advisor or manager providing guidance to a person occupying public office or a prominent position.
   • The governor received guidance on how to best disseminate key information to the public from her handler.
4. A subroutine that handles a particular situation such as an event or exception.
   • If the expression is a throw, we unwind the stack seeking a handler expression. - 2006, Hans-Wolfgang Loidl, Trends in Functional Programming, volume 5, page 62: