J. Wellington Wimpy, generally referred to as Wimpy, is one of the characters in the long-running comic strip Popeye, created by E. C. Segar and originally called Thimble Theater, and in the Popeye cartoons based upon the strip. Wimpy was one of the dominant characters in the newspaper strip, but when Popeye was adapted as an animated cartoon series by Fleischer Studios, Wimpy became a minor character; Dave Fleischer said that the character in the Segar strip was "too intellectual" to be used in film cartoons.

Hamburgers are Wimpy's all-time favorite food, and he is usually seen carrying or eating one or more at a time – e.g. in Popeye the Sailor Meets Sindbad the Sailor he is seen grinding meat or eating burgers almost the entire time – however, he is usually too cheap to pay for them himself. A recurring joke involves Wimpy's attempts to con other patrons of the diner into buying his meal for him. His best-known catchphrase started in 1931 as "Cook me up a hamburger. I'll pay you Thursday." In 1932, this then became the famous "I'll gladly pay you Tuesday for a hamburger today". This phrase is now commonly used to illustrate financial irresponsibility and still appears in modern comedies such as The Drew Carey Show and The Office. The initial part of the phrase was even the title of season 4's episode 6 of Cheers, 'I'll Gladly Pay You Tuesday'.

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