'recluse' originates from Latin, specifically the word 'reclusus', where 're-' meant 'back' and 'claudere/cludere' meant 'to shut or close'.

'recluse' came into English via Medieval Latin/'reclusus' (and through Old French influence), meaning 'shut off' or 'confined', and eventually became the modern English noun 'recluse'.

Initially it meant 'shut off or confined'; over time it evolved to mean specifically 'a person who shuts themselves off from society' (a solitary, withdrawn person).