What is "sisymbrium officinale"

Mustard \Mus"tard\, n. [OF. moustarde, F. moutarde, fr. L. mustum must, -- mustard was prepared for use by being mixed with must. See Must, n.]

1. (Bot.) The name of several cruciferous plants of the genus Brassica (formerly Sinapis), as white mustard ( Brassica alba), black mustard ( Brassica Nigra), wild mustard or charlock ( Brassica Sinapistrum).

   Note: There are also many herbs of the same family which are called mustard, and have more or less of the flavor of the true mustard; as, bowyer's mustard ( Lepidium ruderale); hedge mustard ( Sisymbrium officinale); Mithridate mustard ( Thlaspi arvense); tower mustard ( Arabis perfoliata); treacle mustard ( Erysimum cheiranthoides).

2. A powder or a paste made from the seeds of black or white mustard, used as a condiment and a rubefacient. Taken internally it is stimulant and diuretic, and in large doses is emetic.

   Mustard oil (Chem.), a substance obtained from mustard, as a transparent, volatile and intensely pungent oil. The name is also extended to a number of analogous compounds produced either naturally or artificially.

Sisymbrium officinale, known as hedge mustard, is a plant in the family Brassicaceae. It is found on roadsides and wasteland, and as a weed of arable land. A native of Europe and North Africa, it is now well-established throughout the world.

It is distinct from the mustard plants which belong to the genus Brassica. S. officinale is similar to other Sisymbrium, but differs in its tall, erect stems with tiny flowers and fruits that are compacted parallel to the stem instead of hanging free.

Hedge-mustard is food for the caterpillars of some Lepidoptera, such as the small white ( Pieris rapae).