be somebody’s department
idiomPart ofdepartment
be somebody’s department — idiom
1. This means that a particular area or topic is someone's responsibility or area o
1.idiom
Definition
This means that a particular area or topic is someone's responsibility or area of expertise.
Example
If you need help with the computer, ask Maya; that's her department.
Why are you asking me about cooking? That's definitely not my department.