- the bulb of the sea onion, Urginea maritima, of the lily family, cut into thin slices and dried, and used in medicine chiefly as an expectorant.
- the plant itself.
- any related plant of the genus Scilla.
- See sea squill
- the bulb of the sea squill, formerly used medicinally as an expectorant after being sliced and dried
- any Old World liliaceous plant of the genus Scilla, such as S. verna (spring squill) of Europe, having small blue or purple flowers
