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

• Lexulous
• Wordscraper
• Wordosaur

v. Present participle of unhappen.

n. A happening that fails to occur; a nonevent.

"Hence statistically the water molecules in the tickled area start "falling apart" as their OH bonds now have much less probability, and so they just start "unhappening" statistically as their OH bonds start vanishing statistically."

happening    unappealing    uncapping    unfastening   

posting    re-ally    pitchmen    coquetting    talking-to