(often + to) to restrict or keep (somebody or something) within certain limits

I had to confine myself to a brief summary

Please confine your questions to matters that are directly relevant

to shut (somebody) up

He had been confined to barracks for insubordination

(+ to) said of an illness, etc: to keep (somebody) in bed, a wheelchair, etc

He was confined to bed with gout

dated to keep (a woman) indoors or in bed around the time of immediately before, during, and just after childbirth