On't

Contraction of 'on' and 'it'.

"Are you going to ask her out?"
"Dude, I'm on't"

On't

spoken way to say don't, sometimes the d is dropped in don't for some speakers while speaking, becoming on't

"I on't think we ought to go into the cave billy"
"I on't think we've filled the car off the $10 of gas Bob"

on't

The word "on't" is essentially "don't" but without the "D"

I on't know.