also: わははは · わはははは
interjection
muahaha; mwahahaha; bahaha
Internet slang for a loud, often villainous or triumphant laugh. The number of は can vary for emphasis.
わはは、ついに世界征服だ！
Mwahahaha, world domination at last!
わはは、そんなの簡単だよ。
Bahaha, that's easy.
Onomatopoeic laughter, with the initial わ giving a wide, open-mouthed, boisterous quality. The exact origin is uncertain, but it is a natural extension of Japanese laughter sounds.