'Plumb rule' definitions:
Definition of 'plumb rule'
(from WordNet)
noun
A plumb line attached to a narrow board
Definition of 'Plumb rule'
From: GCIDE
- Plumb \Plumb\ (pl[u^]m), 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. [1913 Webster]
- 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. [1913 Webster]