Rhombus

from WordNet (r) 3.0 (2006)

rhombus
    n 1: a parallelogram with four equal sides; an oblique-angled
         equilateral parallelogram [syn: {rhombus}, {rhomb},
         {diamond}]

from The Collaborative International Dictionary of English v.0.48

Rhombus \Rhom"bus\, n. [L.]
   Same as {Rhomb}, 1.
   [1913 Webster]

[email protected]