long suit

WordReference Random House Unabridged Dictionary of American English © 2026

long′ suit′, 

1. Games [Cards.]
   • the suit in which the most cards are held in a hand.
   • (in bridge) a suit in which four or more cards are held in a hand.
2. the quality, activity, endeavor, etc., in which one excels:
   Diligence is his long suit.
• 1875–80

Collins Concise English Dictionary © HarperCollins Publishers::

long suit noun

1. the longest suit in a hand of cards
2. a holding of four or more cards of a suit
3. an outstanding advantage, personal quality, or talent