1) Chic Young comic of old 2) Gullible lady 
A dumb Dora is 1920s American slang for a foolish woman. The epithet arose from the vaudeville act of George Burns and his wife, Gracie Allen, In 1924 it was turned into a classic comic strip drawn by Chic Young (of later Blondie fame) and produced by King Features Syndicate. Although this strip was discontinued in 1935, a popular 1960s and 1970s ...
a foolishly simple, stupid, or scatterbrained woman.