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Definition of Drilling fluid
1. Noun. A mixture of clays and chemicals and water; pumped down the drill pipe to lubricate and cool the drilling bit and to flush out the cuttings and to strengthen the sides of the hole. 
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1. Noun. A mixture of clays and chemicals and water; pumped down the drill pipe to lubricate and cool the drilling bit and to flush out the cuttings and to strengthen the sides of the hole.