succor (n.)

c. 1200, socour, earlier socours "aid, help," from Anglo-French succors "help, aid," Old French socors, sucurres "aid, help, assistance" (Modern French secours), from Medieval Latin succursus "help, assistance," from past participle of Latin succurrere "run to help, hasten to the aid of." This is from assimilated form of sub "up to" (see sub-) + currere "to run" (from PIE root *kers- "to run").

The final -s was mistaken in English as a plural inflection and dropped late 13c. The meaning "one who aids or helps" is from c. 1300. Stanyhurst's "Aeneid" has succoress "a female helper." The story that speakeasy queen "Texas" Guinan once greeted her lawyer with "Hello, succor" is, hélas, unconfirmed.

late 13c., socouren, "to help or relieve when in difficulty," from Old French secorer, succurre "to help, assist" (Modern French secourir), from Latin succurrere "to help, assist" (see succor (n.)). Related: Succored; succoring; succorable.