megahit

noun

1. A large success or hit.

   “We settle on our target: a group of women riding around on a Manhattan tour bus and visiting sites featured in HBO's '90s megahit Sex and the City.”

   “[Jean] Twenge […] isn’t necessarily a household name like her sometimes collaborator Jonathan Haidt, a social psychologist and the author of the megahit “The Anxious Generation,” which has spent 75 weeks hovering near the top of the New York Times best-seller list.”