This word is acceptable for play in the UK dictionary that is being used in the following games:

• Lexulous
• Wordscraper
• Wordosaur

n. The property of being contestable or debatable.

"Mr. Zey told him that, if he could pass a physical examination, he could procure a policy, which Mr. Zey would arrange in two years to sell to an investor, once the policy passed the standard "contestability" period, the suit alleges."

convertibility