The Pacman clan thanks you for your support!!
SUP!!!

Paku-paku is the sound of munching something in Japanese. Specifically it's the sound of taking a quick bite out of something and so Pac-Man would be a logical name in Japanese for a character that goes around gobbling up or paku-paku ing around kicking ass.

The working title of the game was Paku-Paku but the game was released as Puckman. Before it came to North America it was changed to Pacman supposedly because they were worried people would deface the P into an F.