a. rare. [f. as if on Gr. *ἐννεαετηρίς a cycle of nine years (f. ἐννέα nine + ἔτος year, after the analogy of τριετηρίς, etc.) + -IC.] Consisting of nine years.
1846. Grote, Greece, II. ii. II. 353, note. The fact … does not establish a knowledge of the properties of the octaeteric or enneaeteric period.
