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the mustard family, of the order Brassicales, a large assemblage of 338 genera and some 3,710 species of mostly herbaceous plants with peppery-flavoured leaves. The family includes many plants of economic importance that have been extensively altered and domesticated by humans. The members' flowers are in the form of a Greek cross, with four petals, usually white, yellow, or lavender, and an equal number of sepals. There are four long and two short stamens and a two-chambered ovary positioned above the other flower parts. The seeds are produced in podlike fruits and often have a mucilaginous coating that swells when wetted.