1. A barricade or obstruction across a road set up to prevent the escape or passage, as of a fugitive or enemy troops.
2. An obstruction in a road, as fallen rocks or trees.
3. Something, such as a situation or condition, that prevents further progress toward an accomplishment.

The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.