Source : Webster's Revised Unabridged Dictionary (1913)

Terete \Te*rete"\, a. [L. teres, -etis, rounded off, properly,
   rubbed off, fr. terere to rub.]
   Cylindrical and slightly tapering; columnar, as some stems of
   plants.

Source : WordNet®

terete
     adj : especially of plant parts; cylindrical and tapering