Eruca sativa (syn. E. vesicaria subsp. sativa (Miller) Thell., Brassica eruca L.), is an edible annual plant, commonly known as salad rocket, roquette, rucola, rugula; or, in the United States, where it is very popular, arugula. Salad rocket (arugula) is sometimes conflated with Diplotaxis tenuifolia, the perennial wall rocket, another plant of the Brassicales family, which in the past was used in the same manner. Salad rocket is a species of Eruca native to the Mediterranean region, from Morocco and Portugal in the west to Lebanon and Turkey in the east. Eruca sativa differs from E. vesicaria in having early deciduous sepals. Some botanists consider it a subspecies of Eruca vesicaria: E. vesicaria subsp. sativa. Still others do not differentiate between the two. The Latin adjective sativa in the plant's binomial is derived from satum, the supine of the verb sero, meaning "to sow", indicating that the seeds of the plant were sown in gardens.
Salad rocket grows 20–100 centimetres (8–39 in) in height. The leaves are deeply pinnately lobed with four to ten small lateral lobes and a large terminal lobe. The flowers are 2–4 cm (0.8–1.6 in) in diameter, arranged in a corymb in typical Brassicaceae fashion; with creamy white petals veined with purple, and with yellow stamens; the sepals are shed soon after the flower opens. The fruit is a siliqua (pod) 12–35 millimetres (0.5–1.4 in) long with an apical beak, and containing several seeds (which are edible). The species has a chromosome number of 2n = 22.
Vernacular names include salad rocket, garden rocket, or simply rocket (British, Australian, Canadian, South African and New Zealand English), eruca, and arugula (American English). All names ultimately derive from the Latin word eruca, a name for an unspecified plant in the family Brassicaceae, probably a type of cabbage.