Also called plumb bob. a piece of lead or some other weight attached to a line, used for determining perpendicularity, for sounding, etc.; the bob of a plumb line.
something that weighs down or depresses.

verb (used without object)

to plunge.

Origin of plummet

1350–1400; (noun) Middle English plommet < Middle French, diminutive of plomb lead; (v.) derivative of the noun See plumb, -et
Related formsun·plum·met·ed, adjective

Synonyms for plummet Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for plummet

Contemporary Examples of plummet

Historical Examples of plummet

  • And love was the plummet dropped down into the deeps of him where like had never gone.

    White Fang

    Jack London

  • Oh, is there any plummet to sound the depths of a mother's love?

    Debts of Honor

    Maurus Jkai

  • No plummet ever sank so deep as Jamie sank the thoughts of those few months.

    Pirate Gold

    Frederic Jesup Stimson

  • Her singles were perfectly round, and as flat at the top as if laid with a plummet.

  • This line, with a plummet, is mentioned by Lucilius; and was the sund-gyrd of the Anglo-Saxons.

    The Sailor's Word-Book

    William Henry Smyth

British Dictionary definitions for plummet


verb -mets, -meting or -meted

(intr) to drop down; plunge


another word for plumb bob
a lead plumb used by anglers to determine the depth of water

Word Origin for plummet

C14: from Old French plommet ball of lead, from plomb lead, from Latin plumbum
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for plummet

late 14c., "ball of lead, plumb of a bob-line," from Old French plomet "graphite, lead; plummet, sounding lead," diminutive of plom "sounding lead" (see plumb (n.)).


1620s, "to fathom, take soundings," from plummet (n.). Meaning "to fall rapidly" first recorded 1933, perhaps originally among aviators. Related: Plummeted; plummeting.

Online Etymology Dictionary, © 2010 Douglas Harper