duo (
http://definr.com/duo)
n 1: two items of the same kind [syn:
couple,
doubleton,
pair,
twosome,
twain,
brace,
span,
yoke,
couplet,
distich,
duet,
dyad,
duad]
2: two performers or singers who perform together [syn:
duet,
duette]
3: a pair who associate with one another; "the engaged couple";
"an inseparable twosome" [syn:
couple,
twosome,
duet]
4: a musical composition for two performers [syn:
duet,
duette]