Cantankerous a. : Perverse; contentious; ugly; malicious.

Example:
How can we prevent our old people from getting Cantankerous?

Taxonomy
Merriam-Webster Online Dictionary, ker, Dictionary, webster, Word Games, Webster Online Dictionary with audio pronunciations, thesaurus, glossary, english, language, ESL, adjective, Etymology, contack, contention, mule, ly, adverb.

Defination from the web:
cantankerous from the Merriam-Webster Online Dictionary with audio pronunciations, thesaurus, Word of the Day, and word games. ... difficult or irritating to deal with <a cantankerous mule> — can·tan·ker·ous·ly adverb. — can·tan·ker·ous·ness noun. Learn more about "cantankerous" ...