A girl with a very sexy body but an unattractive face... This phrase is generally uttered by men who examine the posterior of a lady as they drive by, On the approach they say "Oooohhh" and if her face does not match the beauty of her posterior as they pass they will say "Naaaaaa", hence Una.
Used to describe a person that is very polite or Charming for their own gain
Example Business people can be charming or "Sweet" to customers.If customers see them as igornant or "Sour" they will not shop there Hence the phrase Ya wont catch Flies with Vinegar