What is a triglyph?

A triglyph is a rectangular, vertically grooved block in the frieze of the Doric order. Triglyphs alternate with metopes, and together they form the characteristic Doric frieze. The word comes from the Greek triglyphos, “thrice-grooved”. In the classical explanation, already given by Vitruvius, triglyphs are stone versions of the beam ends of earlier timber temples.

Parts

• Grooves: a triglyph has two full vertical grooves (glyphs) in the middle and a half-groove at each edge. This leaves three raised vertical bands: hence the “three”.
• Regula and guttae: directly below each triglyph, on the architrave, is a narrow strip called the regula, with a row of small cone-shaped drops beneath it: the guttae.
• Mutules: on the underside of the cornice above are flat blocks studded with guttae, the mutules, spaced in rhythm with the triglyphs and metopes.
• Metopes: the panels between the triglyphs, plain or carved in relief.

Placement and the corner problem

As a rule there is one triglyph over each column and one over the centre of each intercolumniation. On Greek temples, however, the frieze must end in a triglyph at the corner. Because the architrave is thicker than the triglyph is wide, that corner triglyph cannot also sit centrally over the corner column. This is the Doric corner problem (angle conflict). Greek builders usually solved it by setting the corner columns closer together (angle contraction). The Romans simply centred the triglyph over the column and left a part-metope at the corner.

Uses

Triglyphs appear on Greek and Roman temples, but also on Neoclassical and Greek Revival buildings: gateways, porticoes, monuments, and even interior cornices and chimneypieces.

Practical tips

• Recognising it: a frieze of alternating grooved blocks and flat panels means the Doric order. Ionic and Corinthian friezes have no triglyphs.
• For restoration or new classical work: always proportion triglyphs to the column diameter and bay spacing, or the rhythm of frieze and columns will not line up.

Related terms

• Metope
• Doric
• Frieze
• Architrave
• Entablature
• Ionic order

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