Source : Webster's Revised Unabridged Dictionary (1913)

Acicular \A*cic"u*lar\, a.
   Needle-shaped; slender like a needle or bristle, as some
   leaves or crystals; also, having sharp points like needless.
   {A*cic"u*lar*ly}, adv..

Source : WordNet®

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