The Collaborative International Dictionary of English v.0.48:
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. [1913 Webster]WordNet (r) 3.0 (2006):
fibrillose adj 1: covered with fibrils more or less evenly disposed