Source : Webster's Revised Unabridged Dictionary (1913)

Longanimity \Lon`ga*nim"i*ty\, n. [L. longanimitas; longus long
   + animus mind: cf. F. longanimit['e].]
   Disposition to bear injuries patiently; forbearance;
   patience. --Jer. Taylor.

Source : WordNet®

longanimity
     n : good-natured tolerance of delay or incompetence [syn: {patience},
          {forbearance}] [ant: {impatience}]