Source : Webster's Revised Unabridged Dictionary (1913)

Fibrillose \Fi*bril"lose\ (? or ?), a.
   Covered with hairlike appendages, as the under surface of
   some lichens; also, composed of little strings or fibers; as,
   fibrillose appendages.

Source : WordNet®

fibrillose
     adj : covered with fibrils more or less evenly disposed