Retire comes from French retirer — 'to pull back, to withdraw'. Originally a military term for retreating, it shifted to mean withdrawing from working life in the 17th century.
To leave one's job and cease to work, especially upon reaching a certain age; to withdraw to a quiet or private place.
From Middle French retirer meaning 'to withdraw, to pull back', composed of re- 'back' + tirer 'to draw, to pull'. The French tirer likely comes from a Vulgar Latin *tīrāre or from a Germanic source. The original English sense was military — to retire was to withdraw troops from the battlefield. The sense of withdrawing from working life appeared in the 17th century, framing the
Retire was originally a military command. To retire troops was to pull them back from the front line — a strategic withdrawal, not a surrender. When we speak of retiring from a career, we are using the language of battlefield retreat. The phrase 'to retire for the night' is even older: it simply meant to pull back to your private chamber