A blockbuster is a very successful movie that lots of people want to see. It's also used more broadly to describe anything that becomes incredibly popular and generates a lot of excitement.
When we talk about a new TV show or book as a blockbuster, it means that it's really well-known and lots of people are talking about it. For example, if someone says "The new sci-fi series is a blockbuster," they mean it's a huge hit with viewers. The word can also be used to describe something that breaks records or achieves great success in its field – like a company that becomes a billion-dollar blockbuster after just one year of business.
How common is "blockbuster"?
Word blockbuster is considered uncommon in modern English. It has a balanced usage among all categories: speech, fiction, newspapers and academic texts.
Definitions
noun
A high-explosive bomb used for the purposes of demolishing extensive areas, such as a city block.
(informal) Something, such as a film or book, that sustains exceptional and widespread popularity and achieves enormous sales, as opposed to a box office bomb.
Example: He was watching the blockbuster film series Harry Potter.
(informal) Something, especially an event or a film, book or other creative work, that is intended to achieve high sales (perhaps indicated by large budgets or high advertising spending) or that is conceived on a large or epic scale
(slang) Anything very large or powerful; a whopper.
A large firework of the firecracker type; an M-80.
(US) One who engages in blockbusting (technique encouraging people to sell property).