Definition of planetary
1a
: of, relating to, being, or resembling a planet
c
: having a motion like that of a planet
planetary electrons
d
: immense
the scope of this project has reached planetary proportions
2a
: of, relating to, or belonging to the earth : terrestrial
3
: having or consisting of an epicyclic train of gear wheels
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Merriam-Webster unabridged
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The first known use of planetary was in 1607
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