one fell swoop, in

in one fell swoop

All at once, with a single decisive or powerful action. When the economy crashed, thousands lost their jobs, their homes, and their pensions in one fell swoop.
See also: fell, one, swoop
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

one fell swoop, in

Also at one fell swoop. All at once, in a single action, as in This law has lifted all the controls on cable TV in one fell swoop. This term was used and probably invented by Shakespeare in Macbeth (4:3), where the playwright likens the murder of Macduff's wife and children to a hawk swooping down on defenseless prey. Although fell here means "cruel" or "ruthless," this meaning has been lost in the current idiom, where it now signifies "sudden."
See also: fell, one
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
See also: