plummet
UK[ˈplʌmɪt]US[ˈplʌmɪt]
v
to fall or drop straight down at high speed
v
to decrease rapidly in value or amount
Etymology
the word 'plummet' entered english in the late 14th century from the old french 'plommet', meaning a small ball of lead, which was a diminutive of 'plomb', meaning lead. this old french term derived from the latin 'plumbum', the word for lead. the semantic evolution is clear: the original object, a lead weight attached to a line for measuring depth (a plumb line), gave its name to the action of falling swiftly and vertically, like such a weight. by the 17th century, this concrete sense had extended to the figurative meaning of a rapid and steep decline.
Analysis
the word 'plummet' is a simplex loanword from old french. it does not contain separable morphemes in modern english spelling.
Examples
the damaged aircraft began to plummet towards the ocean.
stock prices plummeted after the unexpected economic report.
his spirits plummeted when he heard the disappointing news.