Having three corners or angles; triangular (in plan or in cross-section).

= three-square, adj.

Having three equal sides; equilaterally triangular. Also figurative threefold, triple.

Having three angles; three-cornered, triangular. Also quasi-adv. In the form of a triangle, triangularly.

Three-cornered, triangular. Obsolete.

Having, or arranged in, the form of a triangle; contained by three sides and angles; three-cornered, three-sided.

Of or pertaining to three corners (quot. 1548); having three corners, three-cornered, triangular.

= trilateral, adj.

Triangular in section, triquetrous: now esp. in Zoology and Botany.

three-cornered.

Having three sides, trilateral (either as a plane figure or flat body with three edges, triangular; or as a solid figure or body with three lateral…

= triangulate, adj. 1.

Having three angles, triangular; in later use only in Natural History, applied to parts or structures of triangular form.

Triangular.

= triangular, adj. 1.

Three-sided triangular; in Natural History of triangular cross-section, three-edged, trihedral, triangularly prismatic or pyramidal.

Contained by three sides; three-sided.

Triangular.

Of or pertaining to a trigon or triangle.

With the sense ‘resembling a cocked hat in shape; triangular’.

attributive and in other combinations, as heater-shape, heater-shaped adjs.