Synonyms for Dual (same or very similar meaning)
WordNet sense 1 (having more than one decidedly dissimilar aspects or qualities):
double, threefold, treble, twofold, two-fold, three-fold
WordNet sense 2 (consisting of or involving two parts or components usually in pairs):
duple
WordNet sense 3 (having or involving or consisting of more than one part or entity or individual):
multiple
From the ODE community, based on WordNet
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