Webster's Revised Unabridged Dictionary · 1913

Spall

Spall , noun

[Old French espaule; compare Italian spalla. See Epaule.]

The shoulder. [Obsolete] — Spenser

Spall , noun

[Prov. English spall, spell. See Spale, Spell a splinter.]

A chip or fragment, especially a chip of stone as struck off the block by the hammer, having at least one feather-edge.

Spall , transitive verb

1.
(Mining) To break into small pieces, as ore, for the purpose of separating from rock. — Pryce
2.
(Masonry) To reduce, as irregular blocks of stone, to an approximately level surface by hammering.

Spall , intransitive verb

To give off spalls, or wedge-shaped chips; -- said of stone, as when badly set, with the weight thrown too much on the outer surface.