Call it quits

• Lower or resign
• Resign one's position
• Resign, as an office
• Resign, as a job
• Send down
• Fancy way to resign

Douglas Harper's Etymology Dictionary Word definitions in Douglas Harper's Etymology Dictionary
1610s (figurative), 1640s (literal), from Latin demittere "to send down," from de- (see de- ) + mittere "to send" (see mission ).

The Collaborative International Dictionary Word definitions in The Collaborative International Dictionary
Demit \De*mit"\, n. The act of demitting; also, a letter, certificate, or the like, certifying that a person has (honorably) demitted, as from a Masonic lodge. [Webster 1913 Suppl.] ||