One would argue that Beauty is neither definable nor objective
During 18th century most philosophical accounts of beauty were treated as an objective quality: they located it in the beautiful object itself or in the qualities of that object. This concept of beauty for what I believe is now the reign of our time. If an individuals facial properties are harmonious, it is appealing to look at. Therefore one would claim this individual as beautiful. But this has several setbacks
Properties of beauty are a representation of the expected - meaning that beauty has been presented to society from both a subconscious & conscious level. If one does not meet the criterias of what beauty is then this person is not beautiful. This representation is not valid because of various perceptions & expectations from each individual. If beauty is objective, then each individual would have the same perception of that object.
Beauty in itself is the response of the beholder in its own mind. I firmly do not believe in the physicality of beauty because beauty in itself does manifest in reality but in our own being.
Whenever someone claims that a certain individual is beautiful or ugly I sit down, sip my tea, and shake my head of disapproval.