long suit(redirected from one's long suit)
A subject, activity, or field, at which someone is particularly skilled or adept. Working with computers was never my long suit, so this receptionist position is going to be a real challenge for me. Movie trivia is one of Sam's long suits, so I think we should ask her to be on our pub quiz team.
One's strong point or advantage, as in Organizing has never been Nancy's long suit. This expression alludes to whist, bridge, and other card games in which holding numerous cards in a single suit may convey a strong advantage. [c. 1900]