1590s, "of or pertaining to a planet;" see planet + -ary. Perhaps from or based on Late Latin planetarius "pertaining to a planet or planets," but according to OED this is attested only as a noun meaning "an astrologer." Planetary nebula, so called for its shape as seen through a telescope, attested from 1785.
neither national nor continental but planetary
planetary motion
planetary year
the planetary tilt
a planetary vagabond
Planck
plane
planeness
planet
planetarium
planetary
planetoid
plangent
plani-
planisphere
plank
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