Send down

• Resign, as an office
• Relinquish, as an office
• Relinquish office
• Abdicate
• Resign, as a position
• Step down
• Resign, as a job
• Withdraw from office

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"\, v. i. [F. d['e]mettre to remove, se d['e]mettre to resign; d['e]- (L. dis-) + mettre to put, fr. L. mittere to send. Cf. Dismiss .] To lay down or relinquish an office, membership, authority, or the like; to resign, as from ...