This sound is widely linked to the 2010 film Inception and the trailer style it helped popularize. Online, people usually call it the Inception horn, Inception dun or braaam. The huge low-end blast became a shorthand for cinematic drama in trailers, parody edits and reaction memes, especially when creators want to make a small moment feel absurdly important. Its staying power comes from how instantly recognizable and easy it is to time with cuts, zooms and reveal captions.