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definitions

leaf mustard

noun
  1. See under mustard(def 2).

mustard

[muhs-terd]
noun
  1. a pungent powder or paste prepared from the seed of the mustard plant, used as a food seasoning or condiment, and medicinally in plasters, poultices, etc.
  2. any of various acrid or pungent plants, especially of the genus Brassica, as B. juncea (leaf mustard), the leaves of which are used for food and B. nigra (black mustard), the chief source of commercial mustard, and Sinapis alba (white mustard).Compare mustard family.
  3. nitrogen mustard.
Idioms
  1. cut the mustard, Slang. to reach or surpass the desired standard of performance: a pitcher who cuts the mustard with his fastball.

Origin of mustard

1300–50; Middle English < Old French moustarde a relish orig. made of mustard seed and must, equivalent to moust must2 + -arde -ard
Can be confusedmuster mustard
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for leaf mustard

mustard

noun
  1. any of several Eurasian plants of the genus Brassica, esp black mustard and white mustard, having yellow or white flowers and slender pods and cultivated for their pungent seeds: family Brassicaceae (crucifers)See also charlock
  2. a paste made from the powdered seeds of any of these plants and used as a condiment
    1. a brownish-yellow colour
    2. (as adjective)a mustard carpet
  4. slang, mainly US zest or enthusiasm
  5. cut the mustard slang to come up to expectations

Word Origin for mustard

C13: from Old French moustarde, from Latin mustum must ², since the original condiment was made by adding must
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 leaf mustard

mustard

n.

late 13c. (late 12c. as a surname), from Old French mostarde "mustard, mustard plant" (Modern French moutarde), from moust "must," from Latin mustum "new wine" (see must (n.1)); so called because it was originally prepared by adding must to the ground seeds of the plant to make a paste. As a color name, it is attested from 1848.

Mustard gas, World War I poison (first used by the Germans at Ypres, 1917), so called for its color and smell and burning effect on eyes and lungs; chemical name is dichlordiethyl sulfide, it contains no mustard, and is an atomized liquid, not a gas. To cut the mustard (1907, usually in negative) is probably from slang mustard "genuine article, best thing" (1903) on notion of "that which enhances flavor."

I'm not headlined in the bills, but I'm the mustard in the salad dressing just the same. [O.Henry, "Cabbages and Kings," 1904]
Online Etymology Dictionary, © 2010 Douglas Harper
Idioms and Phrases with leaf mustard

mustard

see cut the mustard.

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.