be (one's) pigeon

To be one's area of expertise or responsibility. Primarily heard in UK, Australia. I can't approve expense reports, but Betty can—that's her pigeon.

Name	Pronounced	Usage
Bobette
Gervais	zher-VE	French
Lysistrata	-	Ancient Greek (Latinized)
Wit	VEET	Polish
SeÒRas	SHO-rahs	Scottish
Seetha	-	Tamil