an impenetrable barrier to communication or information especially as imposed by rigid censorship and secrecy; used by Winston Churchill in 1946 to describe the demarcation between democratic and communist countries
take the place or move into the position of; "Smith replaced Miller as CEO after Miller left"; "the computer has supplanted the slide rule"; "Mary replaced Susan as the team's captain and the highest-ranked player in the school"
an embankment built around a space for defensive purposes; "they stormed the ramparts of the city"; "they blew the trumpet and the walls came tumbling down"
having the function of uniting a group of similar things; "the Democratic Party is an umbrella for many liberal groups"; "under the umbrella of capitalism"
a formation of military planes maintained over ground operations or targets; "an air umbrella over England"
a lightweight handheld collapsible canopy
covering or applying simultaneously to a number of similar items or elements or groups; "an umbrella organization"; "umbrella insurance coverage"
shut out from view or get in the way so as to hide from sight; "The thick curtain blocked the action on the stage"; "The trees obstruct my view of the mountains"
hinder or prevent the progress or accomplishment of; "His brother blocked him at every turn"