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 rancorouscankerous), from Anglo-Norman contec, possibly from Latin contāctus, past participle of contingere, to touch. See contact.]

The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.