any condition that makes it difficult to make progress or to achieve an objective
同义词：barrier
a barrier set up by police to stop traffic on a street or road in order to catch a fugitive or inspect traffic etc.
同义词：barricade
英汉双解词典包含3185865条英汉词条，基本涵盖了全部常用单词的翻译及用法，是英语学习的有利工具。