πεντετηρίς

ίδος, ἡ
A. term of five years, διὰ πεντετηρίδος every fifth year (inclusively), Hdt. 3.97, 4.94.
II. festival celebrated every fifth year (inclusively), Id. 6.111, Th. 3.104, IG 12.84.6, 32, 22.1172.27.
Liddell, Scott & Jones
A Greek-English Lexicon, 1940
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