1748: plummet (and plumb) Sep 27, 2019

Of course, a pound of feathers weighs as much as a pound of lead—from the classic riddle—but lead is famous for being heavy. Indeed, the word 'plummet' comes from the word 'plommet' (diminutive of 'plomb') meaning 'small lead'.  Initially, the noun meant a steep drop, like it does now, but also was the nominal form of 'plumb', meaning 'to measure depth' i.e. 'plummet' was a measurement of depth. The word has only been used as a verb since the '30's, though this is now quite popular.
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