Green’s Dictionary of Slang

1. excrement; lit. and fig. [shit n. (1a)].

2002		D. Shaw ‘Dead Beard’ at www.asstr.org 🌐 You still went ahead and dropped him in the brad pitt with the barnaby rudge.
2015		N. Cummins Tales of the Honey Badger [ebook] It was a perfect hiding place from which to scare the living Brad Pitt out of any poor bugger that thought they’d take some time out to enjoy the serenity.

2. an act of defecation [shit n. (1b)].

1999		Roger’s Profanisaurus 3 in Viz 98 Oct. 5: Brad rhym. slang. A dump. As in ‘Give me the paper, will you, I’m off for a Brad Pitt’.
2000		N.Y. Post 7 June 10/5: Celebrity culture has overtaken Britain’s rhyming slang [...] can you guess what Brad Pitt means to a Cockney?
2021		Betoota-isms 252: ‘Just heading to the portaloo, gotta take a Brad Pitt’.

3. (Irish, also bradleys) in pl., armpits.

2003

Dublin Dict. 🌐 Bradleys: Means underarms, derives from Brad Pitt’s – armpits.