Sushi is a Japanese dish consisting of boiled round grain rice flavored with vinegar mixture ('sushi-meshi'), eaten normally with fish, raw or cooked.
In 1997, after SG-1 found that Daniel Jackson did not die during the mission to Oannes, during the journey back to the Stargate, Daniel said that he would tell them everything, and Colonel Jack O'Neill joked that he could tell them while they ate sushi. (SG1: "Fire and Water")