Source : Webster's Revised Unabridged Dictionary (1913)

Acerose \Ac"er*ose`\, a. [(a) L. acerosus chaffy, fr. acus, gen.
   aceris, chaff; (b) as if fr. L. acus needle: cf. F.
   ac['e]reux.] (Bot.)
   (a) Having the nature of chaff; chaffy.
   (b) Needle-shaped, having a sharp, rigid point, as the leaf
       of the pine.

Source : WordNet®

acerose
     adj : narrow and long and pointed; as pine leaves [syn: {acerate},
            {acicular}, {needle-shaped}]