How would you explain the difference between a character (in a movie or television show) being sexy versus being sexualized?

To me, if a character has been sexualized, it means that there have been inappropriate sexual characteristics or actions added to their persona. For example, a 14 year old wearing a push-up bra and excessive make up when it has nothing to do with the character or what they do within the plot. Or creating a great female character for an anime but “dressing” her very provocatively. If any of you have seen “Ghost in the Shell”, think of the charcter of the Major. She’s very intelligent, strong, complex and interesting. She is drawn in clothes that make her look like a hooker.

Any ideas on how to explain this in a better fashion?