Planeetoilla

Planeetoilla is a Finnish grammatical form meaning “on the planets.” It is the adessive plural form of the noun planeetta (planet) and is used to indicate location on multiple planets, either in scientific discussion, education, or fiction. The corresponding singular form is planeetalla (“on the planet”). In general Finnish adessive forms convey where something is located or occurs.

In practice, planeetoilla appears in sentences such as statements about planetary environments, exploration, or habitation. It is common in astronomy texts when referring to conditions or phenomena that exist across more than one planet, and it also appears in science fiction and popular science to discuss hypothetical life, weather, or geology on various worlds. For contrast, elative forms such as planeetoilta (“from the planets”) or singular planeetalla are used for other spatial relations.

Etymology and morphology: planeetoilla is built from planeetta + -lla in plural; Finnish uses adessive -lla/-llä to express “on/at” and -i- pluralization patterns align with the noun’s plural form planeetat in nominative. The word aligns with the standard Finnish inflection system: planeetoilla (on the planets), planeetta (the planet), planeettien (of the planets), planeettala vs. planeetalla illustrate how the base noun changes with case and number.

See also: planeetta, planeettojen (genitive), planeetat as the nominative plural.