1590s, "act of retreating, act of falling back," also "act of withdrawing into seclusion," from French retirement (1570s); see retire + -ment. Meaning "privacy, state of being withdrawn from society" is from c. 1600; that of "withdrawal from occupation or business" is from 1640s.
Solitude is the condition of being absolutely alone, whether or not one has been with others, or desires to escape from them .... Retirement is comparative solitude, produced by retiring, voluntarily or otherwise, from contact which one has had with others. Seclusion is stronger than retirement, implying the shutting out of others from access .... [Century Dictionary]
"confine in a cloister or convent," c. 1400 (implied in cloistered), from cloister (n.). Figurative use, "shut up in retirement from the world," is from c. 1600. Related: Cloistered; cloistering.
1590s, of things, places, etc., "affording retirement from society," from recluse (q.v.) + -ive. By 20c. it was used predominantly of persons, "tending to live a retired life and mix little in society." Related: Reclusively; reclusiveness. Recluse alone formerly served also as an adjective in English (early 13c.).
"cage for birds; place where hawks are put to molt," late 14c., from Old French mue "cage for hawks," especially when molting, from muer "to molt," from Latin mutare "to change" (from PIE root *mei- (1) "to change"). In extended use, "a place of retirement or confinement" (early 15c.). Also as a verb, "to shut up, confine" (mid-15c.).