A stone running through a wall from one side to the other and having two smooth vertical faces; a stone squared or dressed for this purpose. Also…

A square hewn stone for building purposes or for pavement (? so called as resembling in appearance, or serving the same purpose as, a wooden beam)…

? Some kind of worked stone for building purposes.

In this sense often ashlar-stone.

= parpen, n. 1. Also: a coping stone.

= ashlar, n. 1, freestone, n. 1.

stonework, or a block of stone, from which marks left by quarrying, cutting, and dressing have been removed.

concrete in technical use (see 2b). A block or slice of stone of a fixed size; also collective singular, stone cut into scantlings.