1. What does it mean?
집콕 describes staying at home, with the image of being firmly tucked into the house. It can name a quiet evening, a whole weekend, or a longer stretch indoors.
Also written or said as 집콕하다, staying in
2. The nuance
It can be chosen relaxation or a result of circumstances; it does not automatically imply isolation or quarantine. Compounds such as 집콕 취미 describe hobbies enjoyed at home. The word itself does not say whether the speaker feels happy or bored.
3. Examples
“주말에는 집콕하면서 밀린 드라마를 보려고 해.”
I'm planning to stay home this weekend and catch up on shows.
“계속 집콕했더니 바깥바람을 조금 쐬고 싶어졌어.”
After staying in for so long, I felt like getting some fresh air.
Sources
Korea Policy Briefing: language and culture
References support the meaning and usage. Example sentences are written for NoCapWiki.