- barrier, roadblock - any condition that makes it difficult to make progress or to achieve an objective; "intolerance is a barrier to understanding"
--1 is a kind of obstacle, obstruction
--1 has particulars: ideological barrier; language barrier - roadblock, barricade - a barrier set up by police to stop traffic on a street or road in order to catch a fugitive or inspect traffic etc.
--2 is a kind of barrier