a military operation in which enemy forces surround a town or building, cutting off essential supplies, with the aim of compelling the surrender of those inside:Verdun had withstood a siege of ten weeks [as modifier]:siege warfare
an operation in which a police or other force surround a building and cut off supplies, with the aim of forcing an armed person to surrender.
a prolonged period of misfortune:I’ve been having a siege of headaches
lay siege to
conduct a siege of (a place):government forces laid siege to the building figurativethe press laid siege to her apartment
(of a place) undergoing a siege:the fort had been under siege by guerrillas since June figurativewe are under siege from budget cuts
Middle English: from Old French sege, from asegier 'besiege'