su·​per·​mas·​sive ˌsü-pər-ˈma-siv How to pronounce supermassive (audio)
: having a very large mass : extremely or extraordinarily massive
a supermassive black hole

Word History

First Known Use

1937, in the meaning defined above

Time Traveler
The first known use of supermassive was in 1937

Dictionary Entries Near supermassive

Cite this Entry

“Supermassive.” Dictionary, Merriam-Webster, Accessed 26 Jan. 2023.

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