spindle-shaped

from WordNet (r) 3.0 (2006)

spindle-shaped
    adj 1: tapering at each end [syn: {fusiform}, {spindle-shaped},
           {cigar-shaped}]

from The Collaborative International Dictionary of English v.0.48

Spindle-shaped \Spin"dle-shaped`\, a.
   1. Having the shape of a spindle.
      [1913 Webster]

   2. (Bot.) Thickest in the middle, and tapering to both ends;
      fusiform; -- applied chiefly to roots.
      [1913 Webster]