"Homely" what does it mean...?

def: adj. to look in appearance as just plain.

This is my definition of Homely. I have held this to be true for years until FC put the smack down on me because apparently I was insulting some poor lady. In my defense she looked plain. However my wife informed me that I was in fact saying she looked UGLY! Well that was not what I had meant or the outcome that I had desired. So I just usually don't use that word anymore for fear of using it incorrectly.