1. Ill-tempered and quarrelsome; disagreeable: disliked her cantankerous landlord.
2. Difficult to handle: “had to use liquid helium, which is supercold, costly and cantankerous”Boston Globe.
[Perhaps from Middle English contek, dissension (influenced by such words as rancorous, and cankerous), from Anglo-Norman contec, possibly from Latin contctus, past participle of contingere, to touch; see contact.]