A phrase used in conjunction with sporting failure under immense pressure, as if someone soiled themselves after being put to the test and failing miserably. It has originated from the man whom wore brown trousers for over 20 years of his life in Ballymena county Antrim. Needless to say he suffered from being under pressure during pool billiard games.
Person A: The pressure really affected him on that last shot.
Person B: No doubt, he did a Billy Brown Trousers.
Needing to take a dump while making a round trip between two towns and keeping it together until you sneeze right as you get home which results in you Brown-Trousering yourself.
" Dude I made the colossal mistake of having a big ole curry last night while drinking a box of beer. Nina was around and I was totally going to get my leg over until I went to the fridge I farted and started brown-trousering.
When a person (usually a teenager) shits their pants in a watery and explosive manner to escape a drug test appointed by his or her parent or legal guardian changing the color of said person's pants and floor causing a literal shit storm
When my parents pulled out that drug test I knew I was fucked and had no choice but to use The Yung Buddah Brown Trouser Shower Diversion