Fallacious yet widespread and documented beliefs courtesy of Wikipedia.
Sushi does not mean "raw fish", and not all sushi includes raw fish. The name sushi refers to the vinegared rice used in it. Sushi is made with sumeshi, rice which has been gently folded with rice vinegar, salt, and sugar dressing. The rice is traditionally topped by raw fish, cooked seafood, fish roe, egg, and/or vegetables such as cucumber, daikon radish, and avocado. The related Japanese term sashimi is closer in definition to "raw fish", but still not quite accurate: Sashimi can also refer to any uncooked meat or vegetable, and usually refers more to the dish's presentation than to its ingredients. The dish consisted of sushi rice and other fillings wrapped in seaweed is called makizushi, and includes both "long rolls" and "hand rolls".