Meatloaf is a type of food created by combining, among other things, meat and bread.
The resequenced meatloaf served aboard the Enterprise, according to Travis Mayweather, was something to be avoided. (ENT: "Fortunate Son")
While trying to survive in Shuttlepod 1, Trip Tucker had a meatloaf with gravy and mashed potatoes ration. (ENT: "Shuttlepod One")
In 2266, Thanksgiving was being celebrated on board the USS Enterprise. Captain James T. Kirk was irritated that the crew had to eat synthetic meatloaf and asked that it be made to look like a turkey. (TOS: "Charlie X")