The Collaborative International Dictionary of English v.0.48:
Disobligation \Dis*ob`li*ga"tion\, n. 1. The act of disobliging. [1913 Webster] 2. A disobliging act; an offense. [Obs.] --Clarendon. [1913 Webster] 3. Release from obligation. --Jer. Taylor. [1913 Webster]