Etymology From Mickey, a diminutive of the given name Michael, + mouse, referring to the species of the character. Walt Disney chose the name Mickey Mouse in 1928, changing it from Mortimer Mouse at the suggestion of his wife, Lillian, who felt the original name was too formal for the character's playful nature. The derogatory adjectival sense developed in the US after WWII, originally applied to dance music, then broadened.
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Derogatory Of dubious or inferior quality, poorly-run; too easy to be taken seriously, trivial.
"They are putting a Mickey Mouse operation on the ice," added Gretzky, who extended apologies to New Jersey goaltenders Ron Low and Chico Resch.1983 November 21, “Rangers get past Quebec in Overtime”, in Miami Herald:
You mean, somebody who, for example, is a retired Army officer, has been teaching, as you do in the Army about half the time for about 30 years, you mean he couldn't go in and teach in the school' cause he didn't take some Mickey Mouse course in education at a state university?1991 April 20, CNN_Novak:
2 more examples
California (78-67): This is no Mickey Mouse outfit, even though Disney is buying into the team. / The Angels didn't make many changes in personnel during the winter.1996 February 11, Dave van Dyck, “Braves, Indians Are Teams to Beat Again; Series Repeat Appears Likely As Camps Open”, in Chicago Sun-Times, SPORTS, page 18:
Mr. [Kash] Patel said he would not tolerate any more “Mickey Mouse operations,” an official on the call recounted. It was one of his few utterances without profanity, the person added.2025 September 12, Glenn Thrush, Devlin Barrett, Adam Goldman, “Patel and F.B.I. Face Scrutiny as Kirk’s Killer Remains at Large”, in The New York Times, New York, N.Y.: The New York Times Company, →ISSN, →OCLC:
Etymology From Mickey, a diminutive of the given name Michael, + mouse, referring to the species of the character. Walt Disney chose the name Mickey Mouse in 1928, changing it from Mortimer Mouse at the suggestion of his wife, Lillian, who felt the original name was too formal for the character's playful nature. The derogatory adjectival sense developed in the US after WWII, originally applied to dance music, then broadened.