拦阻 is a compound verb meaning 'to obstruct' or 'to hinder'—often implying an active, physical, or deliberate effort to stop someone or something from proceeding. The first character 拦 (lán) means 'to block' or 'to intercept', like standing in someone's path; the second character 阻 (zǔ) means 'to impede' or 'to prevent', often suggesting resistance or difficulty in movement or progress. Together, they emphasize intentional interference, typically used in formal, written, or serious contexts—not casual speech.

This word commonly appears in news reports, legal documents, or descriptions of security measures, protests, or emergencies. It suggests authority or force behind the obstruction: police may 拦阻 protesters, border guards may 拦阻 unauthorized entry, or floodwaters may 拦阻 traffic. Unlike more neutral verbs like 阻止 (to stop) or 阻碍 (to hinder), 拦阻 carries a stronger sense of immediate, on-site intervention and often implies legitimacy or official action.