• WordNet 3.6
    • n Lactuca an herb with milky juice: lettuce; prickly lettuce
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Webster's Revised Unabridged Dictionary
    • n Lactuca (Bot) A genus of composite herbs, several of which are cultivated for salad; lettuce.
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Century Dictionary and Cyclopedia
    • n Lactuca A genus of liguliflorous composite plants, to which the lettuce belongs, type of the subtribe Lactuceæ of the tribe Cichoriaceæ, characterized botanically by a beaked achene and a pappus of delicate and copious bristles in many series. These plants are herbs with milky juice, usually with both radical and cauline leaves, which are generally more or less deeply cut, lobed, or pinnatifld, often with bristly ciliate margins. the cauline commonly with clasping or auricnlate base. About 65 well-authenticated species are known, indigenous in Europe, Asia, Africa, and North America. The garden-lettuce, L. sativa, is scarcely known except in cultivation, but is supposed to be a native of Asia. (See lettuce.) From the European species L. virosa principally is obtained the sedative known as lactucarium, or lettuce-opium. The species of this genus all possess narcotic and sedative properties.
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Chambers's Twentieth Century Dictionary
    • Lactuca (lak-tū′ka) a genus of herbs of the aster family, with milky juice
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Webster's Revised Unabridged Dictionary
L., lettuce. See Lettuce
Chambers's Twentieth Century Dictionary
L. lacteus, milky—lac, lactis, milk; Gr. gala, galaktos, milk.


In literature:

Madrepora lactuca, Pallas, Zooph.
"Narrative of a Survey of the Intertropical and Western Coasts of Australia] [Volume 2 of 2]" by Phillip Parker King
Noticed Lactuca exalata and a Rottlera on the road; more snow has fallen on the hills E.N.E.
"Journals of Travels in Assam, Burma, Bhootan, Afghanistan and TheNeighbouring Countries" by William Griffith
Lactuca virosa (Strong-scented Lettuce) .
"Handbook to the Severn Valley Railway Illustrative and Descriptive of Places along the Line from Worcester to Shrewsbury" by J. Randall
Lactuca Canadensis, Wild Lettuce.
"Seeds of Michigan Weeds" by W. J. (William James) Beal
Lactuca macrantha, C. B. Cl.
"Mount Everest the Reconnaissance, 1921" by Charles Kenneth Howard-Bury