What is "triarchy"

Triarchy \Tri"ar*chy\, n.; pl. Triarchies. [Gr. ?; ? (see Tri-) + ? to rule.] Government by three persons; a triumvirate; also, a country under three rulers.
--Holland.

n. 1 government by three persons; a triumvirate. 2 A country under three rulers.

The theory of triarchy (from the Greek τρι- "three" and ἄρχω arch, "to rule") refers to Fairtlough's proposition that there are three fundamental ways of getting things done in organisations: hierarchy, heterarchy and responsible autonomy.)

• Triarchy, referring the three fundamental ways of getting things done in organizations: hierarchy, heterarchy, and responsible autonomy
• Triarchy of the Lost Lovers, an album by Rotting Christ