φρεατιαῖος
From LSJ
σιγᾶν ἄμεινον ἢ λαλεῖν ἃ μὴ πρέπει → it's better to keep silence than to say what's not appropriate (Menander)
English (LSJ)
α, ον,
A belonging to a well or tank, ὕδωρ Hermipp.39, Thphr.CP2.6.3; φ. ὕδατα, opp. ῥυτά, Plu.2.954c, cf. Arist.Mete.353b26.
German (Pape)
[Seite 1304] zum Brunnen gehörig; ὕδωρ, Brunnen-, Röhrwasser, Hermipp. bei Ath. IV, 124; Plut. qu. nat. 2 prim. frig. 20.