I looked it up. Online.
First thing I saw:
Cute : A girl who is lovely and dreamy and cuddly and shy and beautiful and awwww *druels*
Sure dude. Enjoy yourself.
Now for something more accurate and less 'druely' :
1. Delightfully pretty or dainty.
2. Obviously contrived to charm; precious
Hmm, well I'm not sure if I agree completely with them but they are pretty close definitions. To me, cuteness isn't just being 'a girl who is lovely and...' or 'dainty' (though daintiness is associated to a certain level). Precious is quite close as I use that word on cute people. *grin*
For me cuteness is found in three things: innocence, goodness, and honesty.