Ashlar \Ash"lar\, Ashler \Ash"ler\, n. [OE. ascheler, achiler, OF. aiseler, fr. aiselle, dim. of ais plank, fr. L. axis, assis, plank, axle. See Axle.]

1. (Masonry)
   (a) Hewn or squared stone; also, masonry made of squared or hewn stone.

Rough ashlar, a block of freestone as brought from the quarry. When hammer-dressed it is known as common ashlar. --Knight.
   (b) In the United States especially, a thin facing of squared and dressed stone upon a wall of rubble or brick. --Knight.

Source: Webster's Revised Unabridged Dictionary (1913)