A fork of Rural Dictionary
Showbiz marriage is when two celebrities who are in the same band or cast show a deeper relationship with each other over a longer period of time, like a marriage regardless of both people's actual relationship status. The couple in question is often also referred to as an OTP.
Fan 1: Paul McCartney x John Lennon is my favourite famous couple. Fan 2: I know, it's like a showbiz marriage!