senna

senna, any plant of the genus Sennia (formerly placed in Cassia), leguminous herbs, shrubs, and trees of the family Leguminosae (pulse family), most common in warm regions. Some species are cultivated for ornament, but sennas are best known as medicinal plants. The dried leaves are used as a purgative and are chiefly obtained from S. acutifolia (Alexandria senna) and S. angustifolia (Indian senna); both trees are cultivated especially in S India. The wild senna (S. marylandica), a perennial of the E United States, has been similarly used. Golden shower (S. fistula) of India yields canafistula, a purgative extracted from the fruit pulp. The young shoots of several wild species are used for food and the seeds for a coffee substitute. S. nictitans, a North American herb, is sometimes called wild sensitive plant because its leaves respond to touch as do those of the true sensitive plant, a mimosa. Senna is classified in the division Magnoliophyta, class Magnoliopsida, order Rosales, family Leguminosae.

Any of several plants, especially of the genus Cassia, in the pea family (see legume), mostly of subtropical and tropical regions. Many are used medicinally; some yield tanbark used in preparing leather. Some sennas are among the showiest flowering trees. In the eastern U.S., wild sennas (C. hebecarpa and C. marilandica) grow up to 4 ft (1.25 m) high and have showy spikes of yellow flowers. Some species are Old World shrubs or small trees.

Learn more about senna with a free trial on Britannica.com.

Senna can refer to:

Individuals

• Ayrton Senna (1960–1994), former Brazilian F1 driver and triple World Champion
• Bruno Senna (born 1983), race car driver and nephew of Ayrton Senna
• Danzy Senna (born 1970), novelist
• Marcos Senna (born 1976), Brazilian-Spanish footballer
• Márcio Senna (born 1981), Brazilian footballer, Marcos brother
• Senna Guemmour, German singer and member of Monrose (2006–)

• Fictional characters:
• Senna, the shinigami from the anime movie Bleach: Memories of Nobody
• Senna Refa, a character in the Babylon 5 novel Legions of Fire - Out of the Darkness. She is the daughter of Antono Refa
• Senna is also the name of another, unrelated Centauri woman; the governess seen in Babylon 5: In the Beginning. She was an old retainer of 'House Jaddo'.
• Senna Wales, a witch in the Everworld fantasy series for young adults by K. A. Applegate

Plants

• Senna (genus), a genus of legumes
• Formerly, plants in Cassia (genus) which used to include Senna
• black senna, the Scrophulariaceae genus Seymeria
• bladder sennas, the legume genus Colutea
• scorpion sennas, plants in the legume genera Coronilla and Hippocrepis

Other

• Sanandaj (or Sine), a Kurdish city in western Iran
• Senna (poetic), an exchange of insults found in the Poetic Edda

See also

• Sena