Green’s Dictionary of Slang

Mickey Mouse adj.1

[Mickey Mouse, Walt Disney’s anodyne, albeit hugely successful, cartoon creation, created in 1928; sense 2 very quickly becomes used primarily as sense 3]

1. (orig. US, second-rate, badly made, artificial; thus US black) Mickey Mouse music, commercialized jazz or pop music.

[UK]E. Blair letter 27–27 Aug. in Complete Works X (1998) 495: I think on the whole you [i.e. Henry Miller] have moved too much away from the ordinary world into a sort of Mickey Mouse universe where things and people don’t have to obey the rules of space and time.
B. Ulanov Duke Ellington 126: The field was overrun with ‘Mickey Mouse’ music.
[US]M.A. Crane ‘Miscellany’ in AS XXXIII:3 225: A mickey or Mickey Mouse band is not merely a ‘pop tune’ band [...] but the kind of pop band that sounds as if it is playing background for an animated cartoon.
[US]M. Braly Shake Him Till He Rattles (1964) 18: He couldn’t refuse a job that wasn’t outright mickey-mouse.
[US]T. Southern Blue Movie (1974) 25: They’re Mickey Mouse . . . amateurish [...] bad acting, bad lighting, bad camera, bad everything.
[UK]J. Sullivan ‘Hole in One’ Only Fools and Horses [TV script] I don’t want no Mickey Mouse magistrates! I want the High Court, I want a pukka brief.
[Aus]G. Disher Crosskill [ebook] ‘[O]ut of the car rackets, out of Mickey Mouse crap’.
[US](con. 1970s) G. Pelecanos King Suckerman (1998) 50: He’d have to talk to Bernard about dropping off Micky Mouse bullshit like that.
[Aus]Bug (Aus.) Sept. 🌐 Of course they were typically ungracious after the win, saying it was a Mickey Mouse title which Mundane would soon lose anyway.
[Aus]N. Cummins Adventures of the Honey Badger [ebook] I didn’t know if this [i.e. a tour company] was a Mickey Mouse outfit or if it was ridgy didge. Fortunately it was fair dinkum and they were on the case.
[Aus]C. Hammer Opal Country 264: ‘What sort of mickey mouse detective are you?’.

2. small, miniature.

[US]S.F. News 26 Sept. 22: The big, bad Bears, outweighing their Mickey Mouse rivals by some 20 pounds per man .

3. (orig. US) silly, puerile, contemptible.

[US]H. Simmons Corner Boy 170: He didn’t believe that heaven and hell crap, or [...] the rest of that Mickey Mouse junk.
[US](con. 1958) R. Farina Been Down So Long (1972) 112: It’s not all as Mickey Mouse as you might think.
[US](con. c.1970) G. Hasford Short Timers (1985) 28: What’s this Mickey Mouse shit? Just what in the name of Jesus H. Christ are you animals doing in my squad bay?
[US]N. Proffitt Gardens of Stone (1985) 212: I’m feeling useless in this Mickey Mouse outfit.
[US](con. 1969) N.L. Russell Suicide Charlie 65: We were still mourning the loss of nearly forty men, and nobody cared much for the chickenshit lifer Mickey Mouse crap.
[US]J. Lerner You Got Nothing Coming 130: I’m sure the board won’t appreciate having their time wasted by some trumped-up Mickey Mouse charges.
[US](con. 1960s) J. Ellroy Blood’s a Rover 36: Fistfights, drunk-driving beefs. MIckey Mouse rousts.
[US]J. Ellroy Widespread Panic 6: I got [the charge] mashed down to a Mickey Mouse misdemeanor.

4. (US campus) easy, facile.

[US]M.A. Crane ‘Miscellany’ in AS XXXIII:3 226: A ‘Mickey Mouse course’ means a snap course, or what Princeton undergraduates in my day called a gut course.
[US]Harper’s Mag. Oct. 68: College courses in ‘the movies’ are a kind of trade-school apprenticeship or something easy to relax with (‘Mickey Mouse’ in today’s campus parlance).
[US]W. Safire What’s The Good Word? 300: The Californian ‘mick course’ (not an ethnic slur, but a derivation of ‘Mickey Mouse,’ or ‘inconsequential.’.
[US](con. 1950s) P. Hamill A Drinking Life (1996) 183: Some old salts who [...] knew that a helicopter base in the Florida panhandle was Mickey Mouse duty.
[UK]Guardian Education 19 Feb. 8: [cartoon script] I’m sorry, Miss Smith, but I fear that the appointment of our teacher of GCSE Tourism and leisure is only going to fuel the prejudice that the subject is rather mickey mouse.
[US]J. Hannaham Didn’t Nobody Give a Shit 20: An hoinest answer even to this Mickey Mouse question would bring down [...] drama.

In compounds

Mickey Mouse ears (n.)

(US campus) siren lights on a police car.

[US]J. Wambaugh Choirboys (1976) 154: The ‘Mickey Mouse ears’ on the roof of the police car, which is what students call the siren lights.
Mickey Mouse habit (n.) [habit n. (1)]

(drugs) a limited addiction to or occasional use of heroin.

[US]M. Agar Ripping and Running 155: I’m sittin here with a Mickey Mouse habit myself.
Fitomaro ‘Board to reveal the facts and truths’ Archive 9 Oct. Komulo Families 🌐 So you know ‘mickey mouse habit’? hehehe it means ‘junckie’ or ‘joy boy’ (sort of mild addiction). Oh! The next time to go Tokyo DisneyLand, I ask Mickymouse what his habit is.
Mickey Mouse money (n.)

1. any unfamiliar currency, incl. the UK’s decimal coins in the immediate aftermath of their introduction.

[UK]Partridge DSUE (8th edn) 735/1: later C.20.

2. counterfeit money.

[UK]J. Sullivan ‘To Hull and Back’ Only Fools and Horses [TV script] All that money, it’s Mickey Mouse money.