Webster's Revised Unabridged Dictionary · 1913

Rhomboid

Rhomboid (rom"boid) , noun

[Greek {not transcribed} rhomboidal; {not transcribed} rhomb + e'i^dos shape: compare French rhomboide.]

(Geometry) An oblique-angled parallelogram like a rhomb, but having only the opposite sides equal, the length and with being different.

Rhomboid (rom"boid) , adjective

Same as Rhomboidal.