- a cultivated plant, Lactuca sativa, occurring in many varieties and having succulent leaves used for salads.
- any species of Lactuca.
- U.S. dollar bills; greenbacks.
- any of various plants of the genus Lactuca, esp L. sativa, which is cultivated in many varieties for its large edible leaves: family Asteraceae (composites)
- the leaves of any of these varieties, which are eaten in salads
- any of various plants that resemble true lettuce, such as lamb's lettuce and sea lettuce
