plummet
Concise Oxford English Dictionary © 2008 Oxford University Press:
plummet/ˈplʌmɪt/
▶verb (plummets, plummeting, plummeted) fall or drop straight down at high speed.
■ decrease rapidly in value or amount.
▶noun- 1 a steep and rapid fall or drop.
- 2 a plumb or plumb line.
– origin ME: from OFr. plommet ‘small sounding lead’, dimin. of plomb ‘lead’.
'plummet' also found in these Oxford entries:
