recluse (n.)

c. 1200, "person shut up from the world for purposes of religious meditation," from Old French reclus (fem. recluse) "hermit, recluse," also "confinement, prison; convent, monastery," noun use of reclus (adj.) "shut up," from Late Latin reclusus, past participle of recludere "to shut up, enclose" (but in classical Latin "to throw open"), from Latin re-, intensive prefix, + claudere "to shut" (see close (v.)).