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ἐχθρόν, Hsch. 2 Dim. of ἄλφα, carpenter's square, Eustr.in EN322.18.
[Seite 111] τό, = ἄλφα, Winkelmaaß, von der Gestalt, Eustrat. comm. Arist. Eth. 6, 7.
ἀλφάδιον: «ἐχθρὸν», Ἡσύχ.