The Collaborative International Dictionary of English v.0.48:

Plumose \Plu*mose"\, Plumous \Plu"mous\, a. [L. plumosus, fr.
   pluma feather: cf. F. plumeux.]
   [1913 Webster]
   1. Having feathers or plumes.
      [1913 Webster]

   2. Having hairs, or other parts, arranged along an axis like
      a feather; feathery; plumelike; as, a plumose leaf;
      plumose tentacles.
      [1913 Webster]

WordNet (r) 3.0 (2006):

plumose
    adj 1: having an ornamental plume or feathery tuft [syn:
           plumate, plumed, plumose]