octaeteris means synonym of octennium: An 8-year period, particularly (historical) in Greek calendrical and astronomical calculations. Lexicurio rates it Sui generis — a strength score of 87 out of 100.
octaeteris is pronounced /ˌɑktaɪˈtɪɹɪs/.
Why “octaeteris” is a great word
OCTAETERIS — [Noun] An eight-year cycle used in ancient Greek calendrical and astronomical calculations to synchronize lunar months with the solar year. Borrowed from Ancient Greek ὀκταετηρίς (oktaetērís), from ὀκτώ (oktṓ, "eight") + ἔτος (étos, "year") + -ῐ́ς (-ís, suffix forming nouns). Unlike "octennium," a generic term for any eight-year span, or the "Saros cycle," an eighteen-year eclipse predictor, the octaeteris is a specific, historical instrument of harmony. It is the measured insertion of ninety intercalary days, the bronze gear of a lost mechanism turning, and the patient astronomer squinting at a waxing moon—a fragile, human truce between incommensurate celestial rhythms, a cage built to hold time itself.
noun
- Synonym of octennium: An 8-year period, particularly (historical) in Greek calendrical and astronomical calculations.“The octaëteris, or lunæsolar cycle of eight years, is a form of the lunar reckoning of annual time totally distinct from and independent of the reckoning of solar in the primitive equable calendar.”