noun, noun or participle which takes 'suru', intransitive verb
holding a castle; holing up in a fortress
Historical military term for defending a castle under siege. In modern use, it can refer to barricading oneself in a building or room.
戦国時代、多くの武将が籠城戦を強いられた。
During the Warring States period, many warlords were forced into castle sieges.
犯人
The criminal holed up in the bank and barricaded himself inside.
noun, noun or participle which takes 'suru', intransitive verb
staying indoors; confinement to home
Modern extended use: staying at home for a long period, often voluntarily or due to circumstances like bad weather, illness, or remote work.
台風で週末はずっと家に籠城していた。
Because of the typhoon, I stayed holed up at home all weekend.
彼は試験前になると部屋に籠城して勉強する。
Before exams, he holes up in his room to study.