<p><strong>Noun:</strong></p><ul><li>an obstruction placed across a road, especially of barricades or police cars, for halting or hindering traffic, as to facilitate the capture of a pursued car or inspection for safety violations</li><li>an obstruction on a road, as a fallen tree or a pile of fallen rocks</li><li>a hastily built barricade, as of barbed wire, erected across a road to hold up the advance of an enemy</li><li>an action, condition, etc., that obstructs progress toward an objective: Nationalism is a roadblock to European unity</li></ul><p><strong>Verb (used with object):</strong></p><ul><li>to halt or obstruct with or as if with a roadblock</li></ul>