Professor was the McDonaldland advertising character known for his onion-shaped head and inventor-like role.
Professor appeared among the colorful characters used in McDonald's fictional advertising world. He was generally presented as an intelligent, eccentric figure associated with inventions and explanations, contrasting with characters such as Grimace, Mayor McCheese, and Hamburglar.
McDonaldland gave McDonald's a connected set of characters that could populate television commercials, packaging, and promotional material. The characters helped turn the restaurant into an imaginative setting for children rather than presenting it only as a place to buy food.
Professor is easy to confuse with other McDonaldland figures because the characters shared a bright, cartoon-based visual style. His identifying feature was the onion-shaped head, while Grimace was the large purple character and Mayor McCheese had a cheeseburger head.