The American Heritage® Dictionary of the English Language, 4th Edition
n. An imposing of restrictions or controls: "Advertisers and broadcasters would raise howls of protest against any strong clampdown” ( Wall Street Journal).
n. A sudden repressive or punitive restriction or control
the GNU version of the Collaborative International Dictionary of English
n. sudden restriction on an activity.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
v. repress or suppress (something regarded as undesirable)
n. sudden restriction on an activity
Word Usage
"I do not have an answer for this problem, except to note that it emphasizes the need for a comprehensive early warning system which will tell the regulator that an early clampdown is needed."