Mostly applies to emo and hipster kids. Someone is ugly-hot if:
1. You'd hit it.
2. You'd be embarassed if your friends found out.
3. You'd still hit it if they did.
When you can't decide if a girl is fine or ugly. Sometimes depends on the day. But basically said to a girl who can look good and ugly at the same time.
When a girl is naturally ugly/unattractive, but acquires all the "playing cards" of being attractive in today's world, therefore passing for "hot." Playing cards include, but are not limited to: tight/hugging designer jeans, trendy hairstyle, trendy clothes, hair highlights, etc. Many many girls you see out and about are very ugly-hot.
When someone is rather unattractive before a weight loss, face altercation ( example, nose job, jaw realigning,etc...) was not full of themselves before the transformation, but after becoming so called "hot" or attractive and becomes a major bitch and having major changes in personality, etc.. super judgemental to other.
"Heidi totally got a case of "Ugly-Hot Girl Syndrome" when she got her face done. She is a total bitch now and completely full of herself."