mo

A word that can be used to express almost any negative feeling. Its exact meaning depends on the context, its function is to emphasise the current feeling of the individual who is using it. It can mean sadness or disappointment but in some cases it can also mean sympathy or even astonishment.

Other form of it is "mooo" wich means an intense bad feeling

"Mooo! I have a very bad headache. I feel like im dying"
"Mo, i feel you, bro. Hope you'll feel better soon"

"Why im i still single?"
"I dont know. Im single too. Mo..."