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.
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.
See: float shoe, guide shoe