This word is acceptable for play in the US & UK dictionaries that are being used in the following games:

• Lexulous
• Wordscraper
• Wordosaur

adj. superlative form of canny: most canny.

"Just as the best place to live in Cheltenham is not in a Regency house but opposite one, so the canniest property buyers will go for cheaper towns near spas and so have the best of both worlds."