I. noun an improvised barrier erected across a street or other thoroughfare to prevent or delay the movement of opposing forces. • the police action led to riots, with hundreds of demonstrators building barricades and burning vehicles.
II. verb — [with obj.] 1. block or defend with a barricade • they barricaded the building and occupied it all night.
2. shut (someone) into a place by blocking all the entrances • detainees who barricaded themselves into their dormitory.
III. phrases man (or go to) the barricades strongly protest against or defend something.
– origin late 16th cent.: from French, from barrique ‘cask’, from Spanish barrica; related to barrel (barrels often being used to build barricades).