patient endurance of hardship, injuries, or offense; forbearance.
If your beauteousness scorns me, if your worth does not favour me, if your disdain is my humiliation, I shall ill be able, albeit I am well furnished with longanimity, to suffer a grief that is not merely intense but protracted. Miguel de Cervantes, Don Quixote, translated by John Rutherford, 2000
Annunziata's eyes clouded. A kind of scorn, a kind of pity, and a kind of patient longanimity looked from them. Henry Harland, My Friend Prospero, 1903
Late Middle English, late Latin, 1400-1450
Longanimity finds its roots in the Latin terms longus meaning "long" and animus meaning "spirit." It entered English in the 1400s.