The name “McDonald's” was shortened from “McDonald's Famous Hamburgers” in the 1950s.
Richard and Maurice McDonald opened their original restaurant as McDonald's Bar-B-Q in 1940. After reorganizing the business around a limited fast-food menu in 1948, the restaurant used the name McDonald's Famous Hamburgers. The shorter “McDonald's” name became the enduring brand form during the following decade.
The shortened name worked well for expansion because it was brief, distinctive, and directly connected to the founding brothers' surname. It also left room for the Golden Arches and other visual elements to carry more of the brand's meaning.
This history is separate from Ray Kroc's later corporate role. Kroc did not create the McDonald brothers' original name, although his franchising company helped turn McDonald's into a global chain. “McDonaldland” was also a later advertising setting, not the restaurant's corporate name.