/rom"beuhs/ , n. , pl. rhombuses, rhombi /-buy/ .
1. an oblique-angled equilateral parallelogram; any equilateral parallelogram except a square.
2. an equilateral parallelogram, including the square as a special case.
3. a rhombohedron.
[ 1560-70; rhómbos anything that may be spun around, deriv. of rhémbein to revolve ]