Boeing 747 is a two-cabin four-engine aircraft, which is one of the most recognizable passenger planes in the world. It's not for swearing. However, some people may use some online expressions or digital homophones to express some emotions or jokes. For example, the homonym of "piss you off" is "747", but this is not a standard term or meaning. In online chat, "747" is sometimes used to express the meaning of "bye bye" and "goodbye", but this is not the standard usage. In a word, Boeing 747 is not a swear word, but a famous aircraft model.