Following someone closely, often secretly; or the residual waste material left after mining or mineral extraction.
From Old English "tægel" (tail) as a noun, the verb meaning to follow like a tail developed naturally. In mining, 'tailings' are the leftover materials.
Mining tailings are one of the largest waste streams on Earth—the Bingham Canyon copper mine in Utah produced so much waste that its tailing pond is one of the largest water bodies in the state!
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