(third-person singular simple present plummets, present participle plummeting or plummetting, simple past and past participle plummeted or plummetted)
- (intransitive) To drop swiftly, in a direct manner; to fall quickly.
- After its ascent, the arrow plummeted to earth.
From Old English plommet (“ball of lead", "plumb of a bob-line"), recorded since 1382, from Old French plommet or plomet, the diminutive of plom, plum (“lead", "sounding lead"), from Latin plumbum (“lead"). The verb is first recorded in 1626, originally meaning "to fathom, take soundings", from the noun.