παρεῖον

From LSJ

εἰργάζοντο λογάδην φέροντες λίθους καὶ ξυνετίθεσαν ὡς ἕκαστόν τι ξυμβαίνοι → they went to work bringing the stones as they picked them out and put them together as each one happened to fit

Source

German (Pape)

[Seite 512] τό, ungebr. att. Form statt des ion. παρήϊον, w. m. f., u. vgl. παρειά.