mustard

noun

mus·​tard ˈmə-stərd 

1

a

: a pungent yellow condiment consisting of the pulverized seeds of various mustard plants (such as Sinapis alba, Brassica juncea, and B. nigra) either dry or made into a paste or sauce (as by mixing with water or vinegar) and sometimes adulterated with other substances (such as turmeric) or mixed with spices

b

: the seed of a mustard plant used as a spice and in medicine as a stimulant and diuretic, an emetic, or a counterirritant

c

slang : zest

2

: any of several herbs (genera Brassica and Sinapis of the family Brassicaceae synonym Cruciferae, the mustard family) with lobed leaves, yellow flowers, and linear beaked pods

3

: a dark to moderate yellow

mustardy

ˈmə-stər-dē 

adjective

Illustration of mustard

• mustard 2

Examples of mustard in a Sentence

Would you like some mustard on your hot dog?

Recent Examples on the Web

The Freak from The Girls Deli in North Park is a hot sandwich with salty pastrami, brisket, melted jack cheese, bacon, mustard, spicy sriracha mayo, onions, and jalapeños. —Carlos Rico, San Diego Union-Tribune, 18 Feb. 2026

Add ⅓ cup of cornmeal, grated potato, salmon, oysters, celery, parsley, dill, mustard powder, pepper, cayenne (if using) and ½ teaspoon salt. —Kate Bradshaw, Mercury News, 18 Feb. 2026

Coney paczki American Coney Island is serving up Coney Paczki again – a Detroit-style coney dog with chili and mustard that is tucked into a Polish pastry rather than the traditional bun. —Paula Wethington, CBS News, 17 Feb. 2026

The simple sauce made from pantry staples like honey, garlic, and mustard make this recipe worth trying. —Phoebe Evans, Southern Living, 15 Feb. 2026

Word History

Etymology

Middle English, from Anglo-French mustarde, from must must, from Latin mustum

First Known Use

13th century, in the meaning defined at sense 1a

Phrases Containing mustard

• (as) keen as mustard
• cut the mustard
• Dijon mustard
• mustard gas
• mustard plaster
• nitrogen mustard
• white mustard
• wild mustard

Rhymes for mustard

• blustered
• bustard
• clustered
• custard
• flustered
• mustered

Kids Definition

mustard

noun

mus·​tard ˈməs-tərd 

1

: any of several yellow-flowered herbs related to the turnips and cabbages

2

a

: a yellow sharp-tasting condiment consisting of the crushed seeds of various mustard plants either dry or made into a paste or sauce

b

: the seeds of a mustard plant

Medical Definition

mustard

noun

mus·​tard ˈməs-tərd 

1

: a pungent yellow condiment consisting of the pulverized seeds of the black mustard or sometimes the white mustard either dry or made into a paste and serving as a stimulant and diuretic or in large doses as an emetic and as a counterirritant when applied to the skin as a poultice

2

: any of several herbs (genus Brassica of the family Brassicaceae synonym Cruciferae, the mustard family) with lobed leaves, yellow flowers, and linear beaked pods see black mustard sense 1, white mustard

3

a

: mustard gas

b

: nitrogen mustard