Walter L. Rapp (1879–1974) was an architect in Cincinnati, Ohio. He was the "last member of an important Cincinnati architectural dynasty" and one of several prominent Ohio architects to graduate from Massachusetts Institute of Technology (class of 1900). He was part of Rapp & Son after 1901; Rapp, Zettel & Rapp from 1903–1912; Zettel & Rapp from 1913–1930 and Rapp & Meacham from 1931-1958 with Standish Meacham, Rapp's son-in-law. Rapp & Meacham were best known for their residential work, projects written about in a biography on W.L. Rapp authored by his daughter, "Mrs. Standish (Eleanor) Meacham".
Obituaries, Cincinnati Enquirer and Cincinnati Post (3/6/1974); Meacham and Meacham (1982); Painter, AIC (2006), 179