σιγμός

σίζω

A. hissing, as of tortoises, Arist. HA 536a7; as a signal, Plu. 2.593b; in Magic, Plot. 2.9.14; in Gramm., of sibilants, D.T. 631.18, Phld. Po.Herc. 994.33, S.E. M. 1.102.
Liddell, Scott & Jones
A Greek-English Lexicon, 1940
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