(geometry) A right triangle.

(geometry) An obtuse triangle.

(geometry) An acute triangle.

(psychology) A social model of a particular kind of conflict in human interactions, involving three people: a victim, a persecutor (who blames the victim), and a rescuer (who attempts to aid the victim).

plural of red triangle slug

Triboniophorus graeffei, a large air-breathing land slug in the family Athoracophoridae.

(anatomy) Synonym of carotid triangle.