2 definitions
for duad
From The Collaborative International Dictionary of English v.0.48 :
Duad \Du"ad\, n. [See Dyad.]
A union of two; duality. [R.] --Harris.
[1913 Webster]
From WordNet (r) 2.0 :
duad
n : two items of the same kind [syn: couple, pair, twosome,
twain, brace, span, yoke, couplet, distich,
duo, duet, dyad]