(1) (n.) Drilling. The bottom of the casing string, including the cement around it, or the equipment run at the bottom of the casing string. Syn: Shoe. See: Bullhead, Float Shoe, Plug And Abandon. (2) (n.) Drilling. A short assembly, typically manufactured from a heavy steel collar and profiled cement interior, that is screwed to the bottom of a casing string. The rounded profile helps guide the casing string past any ledges or obstructions that would prevent the string from being correctly located in the wellbore. Syn: Shoe. See: Float Shoe, Guide Shoe