περίσχεσις

εως, ἡ
A. surrounding or taking in flank, D.C. 50.31 ; ἡ π. τῶν βαρβάρων the surrounding host of barbarians, Id. 60.30, cf. 40.39.
II. Astrol., planetary blockade, Heph.Astr. 1.15.
Liddell, Scott & Jones
A Greek-English Lexicon, 1940
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