Douché (pronounced dou-shay) is an appropriate response to a retort so spectacularly bad and douchey that it brings everything to a screeching halt.
A random douchebag losing an argument resorts to something along the lines of 'You're such a faggot' while surrounded by progressives, thus making things terribly awkward for everyone. 'Douché' is a wonderful response.
Douché: A retort for when someone corrects or one-ups you in a total douchebag-likefashion that serves only to ruin the moment.
Me: "i had the CRAZIEST time last night! At the Strokes concert, they played a cover of All Along the Watchtower – you know, the Jimi Hendrix song? – anyway, their bass player pulled me up on stage and I sang the chorus with the band!! It was fucking amazing!!"
Idiot: Actually, Along Along the Watchtower is originally a Bob Dylan song. And it doesn't really have a chorus at all – it's not structured like that."
Used in the same manner as touché, douché is used when a bro is coming at ya but being a douchebag about it, especially when making a personaljab at you.
Levi: Hey guy, saw you got laid last night, nice job!
Patrick: Oh thanks man, it's been long enough!
Levi: Yeah, too bad she was a porker.