The definition of lettuce is a plant in the genus Lactuca with crispy leaves.
(noun)An example of lettuce is the primary ingredient in salads.
See lettuce in Webster's New World College Dictionary
noun
Origin: ME letuse < OFr laituës, pl. of laitue < L lactuca < lac (gen. lactis), milk (see galactic): from its milky juice
See lettuce in American Heritage Dictionary 4
noun
Origin:
Origin: Middle English lettuse
Origin: , from Old French laitues
Origin: , pl. of laitue
Origin: , from Latin lactūca
Origin: , from lac, lact-, milk (from its milky juice); see melg- in Indo-European roots
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