Lettuce was a type of vegetable from Earth.
The galley aboard Enterprise NX-01 featured lettuce, salad, and paprika. (ENT: "The Catwalk")
Lettuce was one of the main ingredients of the BLT sandwich, along with bacon and tomato. (VOY: "Equinox")
In 2004, Loomis ordered a Double Superbeef at a Burgerland in Detroit without lettuce. (ENT: "Carpenter Street")
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