The Collaborative International Dictionary of English v.0.48:

Staminodium \Stam`i*no"di*um\ (-n[=o]"d[i^]*[u^]m), n.; pl.
   Staminodia (-[.a]). [NL. See Stamen, and -oid.] (Bot.)
   An abortive stamen, or any organ modified from an abortive
   stamen.
   [1913 Webster]