1. 驯兽员
A handler is someone whose job is to be in charge of and control an animal.

2. 搬运工;操作者;处理者
A handler is someone whose job is to deal with a particular type of object.

1. (sports) someone in charge of training an athlete or a team

Synonym: coachmanager

2. an agent who handles something or someone

e.g. the senator's campaign handlers

3. one who trains or exhibits animals

Synonym: animal trainer