ἀρτιακός

ή, όν, Adv.
A. of even numbers, only in Adv. ‐κῶς, τὸ ἥμισυ ἀ. ὠνομας μένον the half called after the even number, Nicom. Ar. 1.9.
Liddell, Scott & Jones
A Greek-English Lexicon, 1940
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