Official term for the word group used to describe sounds?

[Unregistered]

I need to know what it is, yet I have no idea. I wouldn't even know the official Dutch term, so I can't look it up in a dictionary. Can anybody help me out?

Greetings,

Michiel.

[Mister Micawber]

onomatopoeia?

[Theo]

Hmm... Well, it does seem to describe what I mean yet it doesn't seem to be the exact word... Still, its close enough for me. Thanks a lot :)