The Collaborative International Dictionary of English v.0.48:

Sida \Si"da\, n. [NL., fr. Gr. ??? a kind of plant.] (Bot.)
   A genus of malvaceous plants common in the tropics. All the
   species are mucilaginous, and some have tough ligneous fibers
   which are used as a substitute for hemp and flax. --Balfour
   (Cyc. of India).
   [1913 Webster]

WordNet (r) 3.0 (2006):

Sida
    n 1: large genus of tropical subshrubs or herbs some of which
         yield fibers of mucilaginous substances [syn: Sida,
         genus Sida]