hermit
Meaning: a person who lives apart from society
Usage: The old scholar lived like a hermit, rarely leaving his cabin.
recluse
Meaning: a person who lives in voluntary isolation
Usage: The famous writer became a recluse and avoided public events.
loner
Meaning: a person who prefers to be alone
Usage: Although friendly, he was a loner who preferred studying by himself.
solitary
Meaning: existing or living alone
Usage: A solitary cabin stood at the edge of the frozen lake.
sequestered
Meaning: isolated or set apart from others
Usage: The jury was sequestered during the long trial.