TETRAGONAL

[te.trag.o.nal] adj [LL tetragonalis having four angles and four sides, fr. tetragonum quadrangle, fr. Gk tetragonon, fr. neut. of tetragonos tetragonal, fr. tetra- + gonia angle--more at -gon] (1868): of, relating to, or characteristic of the tetragonal system -- te.trag.o.nal.ly adv