drill bit

n. drilling bit, bit for drilling oil

For the planned skyscraper nicknamed Drill bit see Chicago Spire. Drill bits are cutting tools used to create cylindrical holes. Bits are held in a tool called a drill, which rotates them and provides axial force to create the hole. Specialized bits are also available for non-cylindrical-shaped holes.
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Noun
1. a bit used in drilling for oil
(synonym) drilling bit
(hypernym) bit
(hyponym) core bit

The cutting or boring element used for drilling. See also : Bit