When I was a young lad in the process of learning my first language, I created sound-words based on how I perceived the sounds.
In the style of splash, boom, and pop, here are some I came up with:
Someone running across the yard was bolp bolp bolp...
The flushing of a toilet was glolllllGIT!
A piano being played went dlun dlun dlun
The built in vacuum-operated milking system we used for our cows went kee-lah kee-lah kee-lah
For those who didn't know that I'm goofy sometimes, this is your notification. For those who were suspicious, it's a confirmation, and for this who already knew, this is a reminder.
Does anyone else have made-up onomatopoeia?