ha
From Longman Dictionary of Contemporary Englishhaha, hah /hɑː/ interjection SURPRISEDused when you are surprised or have discovered something interesting Ha! I thought it might be you hiding there!Examples from the Corpusha• Ha! I told you it wouldn't work.From Longman Business Dictionaryhaha written abbreviation for HECTAREOrigin ha (1200-1300) A natural sound