mitre

A covering for the head, worn on solemn occasions by church dignitaries, which has been made in many reincarnations, most recently as a tall cap with two points or peaks.

The surface forming the bevelled end or edge of a piece where a miter joint is made; also, a joint formed or a junction affected by two bevelled ends or edges; a mitral joint.

A cap or cowl for a chimney or ventilation pipe.

A gusset in sewing, etc.

A mitre shell

(historical) A 13th-century coin minted in Europe which circulated in Ireland as a debased counterfeit sterling penny, outlawed under Edward I.

(rare) A square with one triangular quarter missing from the outside.

To unite at an angle of 45°.

To adorn with a mitre.