Like their own worlds, because they are imaginary, Yeti means /ˈjɛti/
It means Abdominal Snowman.
If you wanted to see a picture of a yeti, here it is.
A Yetis is also called the Abominable Snowman. I don't think anyone has ever really seen one in person, but I could be wrong. Difficult to say how they behave with so little info about them...