Goofy made his debut in Mickey’s Review in 1932 under the stage name Dippy Dawg.
His name changed slowly over several years, first to just Dippy, then Dippy the Goof, and then to Goofy by 1939.
Suffering a slight identity crisis, he appeared as Mr. Geef for a while in the 1940s, but this name was short-lived and he finally settled down for the rest of his career as just plain Goofy.