imprisonment

(noun) putting someone in prison or in jail as lawful punishment.

(noun) the state of being imprisoned. Synonyms: captivity, incarceration, immurement. Examples: "He was held in captivity until he died." "The imprisonment of captured soldiers." "His ignominious incarceration in the local jail." "He practiced the immurement of his enemies in the castle dungeon."

(noun) the act of confining someone in a prison (or as if in a prison). Synonyms: internment.