Tawi'Yan
Tawi'Yan was a term in Klingonese meaning "sword-bearer". In a Klingon wedding, the Tawi'Yan was their equivalent of Earth's best man. 

Alexander Rozhenko acted as the Tawi'Yan in his father Worf's wedding to Jadzia Dax in 2374. ()

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Klingonese
Societal classifications