1. strong suit one's most highly developed characteristic, talent, or skill; forte: Patience is not his strong suit.
Etymology: (1860–65)
Definition of 'strong suit'
Princeton's WordNet
1. (noun)strong suit a long suit including high cards
2. (noun)forte, strong suit, long suit, metier, specialty, speciality, strong point, strength an asset of special worth or utility "cooking is his forte"
Definitions of strong suit 
