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Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.
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No pronunciation record was provided for this word.
noun
The point of a body's elliptical orbit about the moon's centre of mass where the distance between the body and the centre of mass is at its minimum.
Definition source: English Wiktionary via Wiktextract
Usage: uncountable
Topics: astronomy, natural-sciences
No example sentence was provided for this meaning.
Synonyms: none provided
Antonyms: none provided
History
From peri- + seleno- + -ium, Latin form of -ion.
