Note: When an external projection is used merely to stiffen a wall, it is a pier.

2. Anything which supports or strengthens. "The ground pillar and buttress of the good old cause of nonconformity." South. Flying buttress. See Flying buttress.

BUTTRESS
But"tress, v. t. [imp. & p. p. Buttressed (p. pr. & vb. n.
Buttressing.]

Defn: To support with a buttress; to prop; to brace firmly.
To set it upright again, and to prop and buttress it up for duration.
Burke.

BUTT SHAFT
Butt" shaft`

Defn: An arrow without a barb, for shooting at butts; an arrow. [Also but shaft.] Shak.

BUTT WELD
Butt" weld`.

Defn: See Butt weld, under Butt.

BUTTWELD
Butt"weld`, v. t.

Defn: To unite by a butt weld.