solitary

An solitary person or thing is alone, without others nearby.

When we talk about someone being solitary, it's usually because they like to spend time by themselves. They might enjoy reading books, going for walks, or doing other activities on their own. It doesn't necessarily mean that they're lonely; some people are just happy with their own company and don't feel the need to be around others all the time. You might also hear the word "solitary" used to describe a place, like a solitary tree standing in an open field, or even a solo traveler who prefers not to join tour groups. In these cases, it's often because they value their independence and freedom to do as they please.