Meanings
plural planemos
- astronomyan astronomical object with enough mass to achieve hydrostatic equilibrium, but not enough to initiate core fusion at any time in its existence. That is, it is rounded in shape and is smaller than a star. Planemos include planets, dwarf planets, and the larger moons of the Solar System (satellite planets), but also sub-brown dwarfs and rogue planets between the stars.
Other groups have also recently identified young, isolated planemos; understanding how such isolated, ultra-low masses form presents a challenge.
2003 December 1, Jacques Lépine, Jane Gregorio-Hetem, Open Issues in Local Star Formation, page 266
Origin
Contraction of planetary-mass object. Coined by Gibor Basri, Professor of Astronomy at the University of California, Berkeley, (UCB) at the 2003 IAU conference.
Full word history & related roots →Translations
German Objekt planetarer Masse
- Objekt planetarer Masseplanemo
Polish planemo
- planemoplanemo
Turkish planemo
- planemoplanemo
Rhymes & wordplay
Anagrams
Cite this entry
planemo. (n.d.). In WatkinsX Dictionary. Retrieved November 2, 2026, from https://dictionary.watkinsx.com/word/planemo
“planemo.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/planemo. Accessed November 2, 2026.
WatkinsX Dictionary, s.v. “planemo,” accessed November 2, 2026, https://dictionary.watkinsx.com/word/planemo.
Source: planemo on Wiktionary, CC BY-SA 4.0.