Pronunciation IPA (key): /ˈhæpənz/ Audio (US)(file) Audio (UK)(file) Verb Plain form happen Third-person singular happens Past tense happened Past participle happened Present participle happening The third-person singular form of happen. What a coincidence. It just so happens to be my birthday today, too. If anyone happens to return my wallet, please call me. Don't worry about it. It happens all the time.Wikiwand - on Seamless Wikipedia browsing. On steroids.