heartburning n 1: intense resentment; "his promotion caused much heartburning among his rivals"
Heartburning \Heart"burn`ing\ (-b[^u]rn`[i^]ng), a. Causing discontent. [1913 Webster]
Heartburning \Heart"burn`ing\, n. 1. (Med.) Same as {Heartburn}. [1913 Webster] 2. Discontent; secret enmity. --Swift. [1913 Webster] The transaction did not fail to leave heartburnings. --Palfrey. [1913 Webster]