duo C1

/ˈdu.oʊ/ Two people who perform, work, or act together.

duet C2+

/duˈɛt/ a musical composition or performance for two performers

deuce C2+

/dus/ a playing card or die showing two; (in tennis) a tied score

dubious C2+

/ˈdubiəs/ hesitating or doubting; of questionable value or truth

doublet C2+

/ˈdʌblɪt/ a close-fitting jacket once worn by men, or one of a pair of like things

dubiety C2+

/duˈbaɪəti/ a feeling of doubt or uncertainty

duple C2+

/ˈdupəl/ consisting of two parts, especially having two beats per measure

duplet C2+

/ˈduplət/ a group of two notes played in the time of three