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[ noun ] a cord from which a metal weight is suspended pointing directly to the earth's center of gravity; used to determine the vertical from a given point

Synonyms

perpendicular

Used in print

(Edward Streeter, The Chairman of the Bored....)

He also bought a huge square of pegboard for hanging_up his tools , and lumber for his workbench , sandpaper and glue and assorted nails , levels and T_squares and plumb_lines and several gadgets that he had no idea how to use or what they were for .

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