Madchester, n. — Green’s Dictionary of Slang

Madchester n.

[the brief but well-publicized period (c.1989–92) when Manchester, rather than London, dominated teen fashion, music and choice of drug consumption. Mad refers to the use of MDMA (cf. ecstasy n.), the drug of choice in the city’s clubs]

Manchester.

1989		Happy Mondays Madchester Rave On EP [single].
2001		Miranda Sawyer Observer 🌐 The film will cover the Manchester scene from Joy Division to Madchester, and it’s the Madchester era that I’m revisiting.
2004		Guardian Weekend 7 Aug. 31/1: These municipal radicals took over the council during the 1980s when [,...] cultural entrepreneurs played midwife to Madchester’s pop renaissance.