BT Yom 37a(50) :גלגלא דהוו משקעי ליה‏ : an irrigation wheel with which they used to lower it [i.e. the laver into a cistern]
See the entire entry for galgal, galgəlā n.m. wheel

BT Yom 37a(50) :גלגלא דהוו משקעי ליה‏ : an irrigation wheel with which they used to lower it [i.e. the laver into a cistern]
See the entire entry for šqˁ vb. to sink