συνίζησις

εως, ἡ
A. subsidence, collapse, of the earth, ἐς τὰ κοῖλα Id. Mu. 396a3 (but γῆ [ἐγένετο] κατὰ συνίζησιν (sc. τοῦ ὕδατος) Sch.Hes. Th. 115); οἰκοδομημάτων Plu. Crass. 2: metaph., Plot. 2.2.1.
2. synizesis, melting of two vowels into one, without alteration of letters, as in πόλεως, μὴ οὐ, etc., EM 735.36, Sch.Heph. 2.1; but = συγκοπή, EM 279.8.
3. compression of air, Hero Spir.Praef.
Liddell, Scott & Jones
A Greek-English Lexicon, 1940
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