sub·​stel·​lar ˌsəb-ˈste-lər How to pronounce substellar (audio)
variants or sub-stellar
of a celestial object
: having less mass than a star : not having the mass required to sustain nuclear fission
Subsequent hunts within young stellar clusters have flushed out droves of brown dwarfs. Prime targets are the Pleiades cluster and star-forming regions in Orion and Taurus, where substellar bodies rival stars in number.Robert Irion
Very often, the most publicized events in astronomy involve the detection of fundamentally new types of objects. The discovery of a substellar object, a "brown dwarf" some dozens of times as massive as Jupiter, falls in this category.Physics Today

Example Sentences

Recent Examples on the Web In Louisiana, the state and the U.S. Army Corps of Engineers—which enters with a substellar reputation, to say the least, given its colossal Katrina failures—is currently pursuing a $50 billion shoreline restoration project, known as the Mid-Barataria Sediment Diversion. Nick Martin, The New Republic, 8 Mar. 2021

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'substellar.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1949, in the meaning defined above

Time Traveler
The first known use of substellar was in 1949

Dictionary Entries Near substellar

Cite this Entry

“Substellar.” Dictionary, Merriam-Webster, Accessed 5 Jun. 2023.

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