τροπιδεῖον

τό
A. = τρόπις, τροπιδεῖα καταβάλλεσθαι to lay the keel, Pl. Lg. 803a; v. l. τροπίδια, cf. Poll. 1.85, Phot.
Liddell, Scott & Jones
A Greek-English Lexicon, 1940
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