retirement (n.) Look up retirement at
1590s, "act of retreating," also "act of withdrawing into seclusion," from Middle French retirement (1570s); see retire + -ment. Meaning "privacy" 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]