(mathematics) The diagonal of a matrix that lies directly below and to the left of the main diagonal.

The fourth of June, the anniversary of the 1989 Tiananmen Square crackdown, known in China as the June Fourth Incident.

(idiomatic, dated, colloquial) I do not believe what you said.

(anatomy) A branch of the first portion of the maxillary artery that is the largest artery supplying the dura mater, enters the cranium through the foramen spinosum, and divides into anterior and p...