IPA: //ˈsuːpərhɪt//
KK: /ˈsuːpərhɪt/
A very successful and popular song, movie, or other entertainment that achieves great success.
The movie became a superhit, breaking box office records.
Superhit → It is formed from "super-" (meaning above or over) and "hit" (from Old English "hyttan", meaning to strike or achieve). The word "superhit" refers to a hit that is above the usual level of success or popularity.
Think of something that is a 'hit' but even 'above' ('super-') the usual level of success — that's why a superhit is an exceptionally successful achievement.