a. Any of various plants of the genus Lactuca of the composite family, especially L. sativa, cultivated for its edible leaves.
b. The leaves of L. sativa, used especially in salads.
2. Slang Paper money.
[Middle English lettuse, from Old French laitues, pl. of laitue, from Latin lactūca, from lac, lact-, milk (from its milky juice); see melg- in the Appendix of Indo-European roots.]
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