Plumb (plŭm), n. [F.
plomb, L. plumbum lead, a leaden ball or bullet; cf. Gr.
mo`lybos, mo`libos, mo`lybdos. Cf.
Plummet, Plunge.] A little mass or weight of lead,
or the like, attached to a line, and used by builders, etc., to
indicate a vertical direction; a plummet; a plumb bob. See Plumb
line, below.
Plumb bob. See Bob, 4. --
Plumb joint, in sheet-metal work, a lap joint,
fastened by solder. -- Plumb level. See
under Level. -- Plumb line.
(a) The cord by which a plumb bob is suspended; a
plummet. (b) A line directed to the center of
gravity of the earth. -- Plumb rule, a
narrow board with a plumb line, used by builders and
carpenters.
Plumb, a. Perpendicular; vertical;
conforming the direction of a line attached to a plumb; as, the wall
is plumb.
Plumb, adv. In a plumb direction;
perpendicularly. "Plumb down he falls."
Milton.
Plumb, v. t. [imp. & p.
p. Plumbed (plŭmd); p. pr. & vb.
n. Plumbing (plŭm"&ibreve;ng).]
1. To adjust by a plumb line; to cause to be
perpendicular; as, to plumb a building or a wall.
2. To sound with a plumb or plummet, as the
depth of water; hence, to examine by test; to ascertain the depth,
quality, dimension, etc.; to sound; to fathom; to test.
He did not attempt to plumb his
intellect.
Ld. Lytton.
3. To seal with lead; as, to plumb a
drainpipe.
4. To supply, as a building, with a system of
plumbing.
