threesome (n.)

• bout
• clover
• contest
• decathlon
• deuce-ace
• doubles
• event
• foursome
• game
• go
• leash
• match
• meet
• pentathlon
• play
• race
• runoff
• shamrock
• singles
• sport
• tercet
• ternary
• ternion
• terzetto
• three
• tierce
• trefoil
• trey
• triad
• triangle
• tricorn
• trident
• trilogy
• trimester
• trine
• trinity
• trio
• triple
• triplet
• tripod
• triptych
• trireme
• triskelion
• triumvirate
• trivet
• troika
• twosome