BT Šab 78a(21) :כל שקייני מסו ומיטללי לבר ממיא דמסו ולא מיטללי‏ : all potions cure and are unabsorbed, except for water which cures and is absorbed
See the entire entry for ˀsy vb. D to heal

BT Šab 78a(21) :כל שקייני מסו ומיטללי, לבר ממיא דמסו ולא מיטללי‏ : all the liquids heal and are made into a covering, except for water, that heals but does not form a covering [Geon.: stay unabsorbed; see DJBA]
See the entire entry for ṭll vb. to cast shade on