If a person is douche bombing, it means they are being unnecessarily douchey. It is when a person is being a douche bag in a situation that does not require it.
There are also variants of the term:

A douche bomber is a person who is well known for douche bombing frequently.

A douche bomb is one statement of unnecessary doucheyness, not to be followed up with another, and sometimes followed with an appology.
Douche bombing:

Guy One: "I dunno, I kind of liked World of Warcraft"
Guy Two: "Faggot"
Guy Three: "Was that really needed?"
Guy Two: "Fuck you, dick"
Guy One: "Whatever, he's just douche bombing"

Douche Bomber:
Guy One: "I dunno, I kind of liked World of Warcraft"
Guy Two: "Faggot"
Guy One: "What?"
Guy Three: "Don't take him seriously, he's a douche bomber".

Douche Bomb:
Guy One: "I dunno, I kind of like World of Warcraft"
Guy Two: "Faggot"
Guy One: "What?"
Guy Two: "I'm sorry for that Douche bomb, that wasn't necessary".
by Staska June 14, 2009
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A person who exceeds the limits of being a douche, douche bag, or even a douche canoe.
dude 1: You suck at this game.
dude 2: Man, I literally picked it up 30 minutes ago.
dude 1: You suck. Just like your mother.
dude 2: Stop being such a fucking douche bomb.
by ninja_carrot November 5, 2009
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Statements made by a douchey person that are absurd.
Douche bomb made by Lane: Rockabilly is the clans music of the red states.

Lane: I know suffering. I DJ’ed in Haiti.
by Ms. Dick Pickles January 24, 2022
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