One of a series of short chamfered, cylindrical, prismatic, rectangular, segmental, or square projecting members in, or forming, a decorative continuous moulding, its axis parallel to the direction of the series, with sometimes two or more rows of this ornament placed one above the other, with the billets of one row alternating with those of the other. It is characteristic of Romanesque architecture. Cylindrical billets resemble short lengths of dowel.
alternating cubical billets, Church of St Augustine, Canterbury, Kent
cylindrical billets, Binham Priory, Norfolk
half-cylindrical and prismatic billets, Church of St Mary de Castro, Leicesterbillet (After Parker)