The sound you make when you are confused, don’t want to do something, are talking to someone, or when you see something weird.

When you have an orgasm and moan

She's sick of your shit bro.....

Ugh

The sound a girl makes when she has "fun"

When you’re stuck at a family gathering, and want to show your mother how you feel.

That expression Captain said in the Week 7 Friday Night Funkin song "Ugh" that was catchy as hell for some reason.