a way to get your attention. usually used in texting when something "high key" happened. it can also be used as a reaction like, "brooooo" "no wayyy" "what?!". can both be as negative and positive, depends on the situation.

Briefly, "the realization that each random passerby is living a life as vivid and complex as your own." Originally from the Dictionary of Obscure Sorrows, which has a lot more beautiful neologism definitions like this you might enjoy.