Green’s Dictionary of Slang

a euph. for fuck n. in its various forms.

1943		M. Harrison Reported Safe Arrival 30: Ole Blanco ’adn’t got muck-all on his chalk-farms.
1960		(con. WWII) G. Sire Deathmakers 46: What the muck are you going to do after the mucking war?
2003		‘Le Comtesse Iridith Satania Bathory’ ‘The X-Mas Gift’ on Pretty Moppet’s Bedroom 🌐 Spike continued walking until he passed another store. On the outside was some sign that said ‘Chanel’ or something, he really didn’t give a muck.