A cafeteria was a self-service restaurant or dining room where customers would select food from counters and take it to their tables.
In 2152, Jonathan Archer invited Trip Tucker to breakfast at 930 in Spacedock's cafeteria, to which Tucker replied that he had been about to ask Archer the same thing. (ENT: "Shockwave")
When Jack Ransom was transformed into a caveman in 2381 and locked in the USS Cerritos cafeteria, he replicated a doll made from churros and carried it around like it was his wife. (LD: "Room for Growth")