a whizz-kid

a young person who is very clever and successful They've taken on some financial whizz-kid who's going to sort all their problems out.

Name	Pronounced	Usage
Lothaire	-	French
Balfour	['bælfə]
Dax	DAKS	English
Bertie	BUR-tee	English
Reinhard	-	German, Ancient Germanic
Shelby	['ʃelbi]