Astronomical/ˌæstrəˈnɑːmɪkl/ Definition 1 of 2Pro Tip 1/3Exaggeration Clue Used to emphasize that something is extremely, perhaps excessively, large or significant. The amount of data we need to process is astronomical. Pro Tip 2/3Not Literal Doesn't always mean related to space; can describe anything very large. He has an astronomical number of followers on social media. Pro Tip 3/3Hyperbolic Often used to express hyperbole or overstate, not always an exact measurement. The lottery jackpot reached an astronomical sum!