Definition of "plumb" [plumb]

• A weight on the end of a line, used to determine water depth. (noun)
• A weight on the end of a line, used especially by masons and carpenters to establish a true vertical. (noun)
• In a vertical or perpendicular line. (adverb)
• Informal Directly; squarely: fell plumb in the middle of the puddle. (adverb)
• Informal Utterly; completely: plumb worn out. See Note at right. (adverb)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "His own dexterity in catching the phrase plumb in the middle gave him a thrill of excitement."
• "Silently, but with unerring certainty, something small, round, and deadly, fell plumb from the library ceiling to where the settle had formerly stood against the hearthstone."
• "The dirt airstrip cut into a grove of black cottonwoods was adequate without being what you could call plumb level or arrow straight."