Webster's Revised Unabridged Dictionary · 1913

Quietus

Quietus , noun

[Late Latin quietus quit, discharged, Latin, at rest, quiet, dead. See Quiet, a., and compare Quit, a.]

Final discharge or acquittance, as from debt or obligation; that which silences claims; (Figuratively) rest; death.
When he himself might his quietus make With a bare bodkin. — Shakespeare