Not straight; crooked, twisted (as when having a deformed mouth, as the mouth of any container no longer being perfectly round).
Don't belittle a person who has a crooked/deformed mouth, lest the same thing happen to you.
(For one's mouth) to become crooked, twisted, not straight; to twist one's mouth (as when signaling disagreement [-an], irritating or teasing s.o. [-redup-an].
Ongoy na pakiyu' behe nu?
Why is your mouth becoming crooked?
If you try to convince people like that, you will just have people twisting their mouths in disagreement.