photobomb noun a photograph with a background that dominates and subverts the intended subject of the photograph US
— urbandictionary.com, 27 June 2008
How’d he know? What’s the–maybe this is the game. What’s the backstory on that photobomb? I think that to get the jump right, they had to practice a few times. — TheBryantParkProject, 15 May 2008