O. umbellatum is a relatively short plant, occurring in tufts of basal linear leaves, producing conspicuous white flowers, in a stellate pattern, in mid to late spring.

O. umbellatum has been depicted in art by artists such as Leonardo da Vinci, and folklore has suggested it originally grew from fragments of the star of Bethlehem, hence its horticultural name.

O. umbellatum is a perennial herbaceous bulbous plant (geophyte), dying back after flowering, to an underground storage bulb.

The following year, it regrows from the often shallow rooted bulbs, which are ovoid with a membranous coat,[2] 15–25 millimetres (1⁄2–1 inch) long and 18–32 mm (3⁄4–1+1⁄4 in) in diameter.

[4] O. umbellatum is scapose, with a glabrous flower stem (scape) that emerges from the leaf tufts later and is about 10–30 cm (4–12 in) in height, tapering at its tip.

The gynoecium has a single pistil with a superior (i. e. above the floral parts) ovary that is ovoid to obovoid, 3–4 mm (1⁄8–3⁄16 in), and longer than the style that extends above it.

[11] In Henry Lyte's 1586 New Herbal (a translation into English of Dodoens' 1554 Cruydeboeck), reference is made to an Ornithogalum as the White Field Onion.

[24] A native of most of Europe,[25] North Africa and western Asia, O. umbellatum has been adopted as an ornamental garden plant from where it has escaped and naturalised widely in North America,[7] where it is considered an aggressive noxious weed of lawns, gardens and no-till agricultural land, which can be difficult to eradicate.

[23] In Europe its range extends from Ireland[26] and Portugal in the west, Italy in the south, north to parts of France and east to Turkey[2][16][18] and the Levant.

[32] The plant, especially the bulb and flowers, contains cardiac glycosides, specifically convallatoxin and convalloside which are toxic to humans and livestock.

[2][6][7] Symptoms of poisoning include nausea, salivation, vomiting, diarrhea, and shortness of breath, as well as pain, burning, and swelling of lips, tongue, and throat.

[41][42] In folklore, the biblical star of Bethlehem is said to have fallen to the earth and shattered into pieces which became the ubiquitous white flowers.

[37] A biblical passage in 2 Kings 6:25 relates an account of a siege in Samaria in which the desperate population consumed the excrement of doves (chiriyonim).

In notes taken by Paul Dietrich Giseke from a lecture by Linnaeus[34] it is suggested that this Stercus Columbarum was in fact the plant Ornithogalum umbellatum, which grew abundantly in Palestine and "unde Anglis Bethlem's Star dicitur" (is known to the English as Bethlem's Star), the white colour of which resembled the excrement of birds, hence the name lac Avium (bird milk or Ornithogalum), and which was still eaten by the poor of that country.