The feeling has often been reduced into the French expression "Je ne sais quois," though because the saying is so hackneyed I think it does little to convey the intensity of the desire. What the expression does do accurately is point out that most men have absolutely no idea what it is about a given woman that they find attractive. Considering how analytical we are, it is surprising how rarely men apply a systematic thought process to such an important element of our lives. Probably this has something to do with the fact that the most powerful examples of this desire (i.e. those easiest to understand) are also the most overwhelming; so that the typical male instinct to "figure it out" is lost in the wave of awe described above. In any case, men are usually at a loss for words in trying to decipher what exactly it is about a woman that seizes their attention.
Extreme attraction is not evoked by any woman in her natural state. It is the cumulative product of many powerful and well though-out preening practices, which have been developed to yield the effect described above. You might even say these practices "evolved," since they are not always improved intentionally, but as their effectiveness increases in attracting men, they have a greater tendency to persist through the fads and social trends, to eventually become classics. But it is the collective effect of these things that takes a woman from average to stunning.
So here is the important point: while these ways of self-presentation are obvious to the woman using them, they are entirely incomprehensible to most men. A woman will know that she looks better because she is in heels, or because she is wearing her best colors, or because she just had her hair done. A man sees all of these things, but understands none of them. All he gets when he sees a woman is a holistic impression of her. That impression is directly controlled by the efforts she has made, and a man will be more or less attracted to her accordingly; but for him, it is still je ne sais quois.
This is the power of subtlety, and it shouldn't be underestimated. It is the same effect that you get when you walk into a room with a heavy atmosphere - for example, a nightclub or high-end restaurant. Every piece of that atmosphere is thought-out and tailored to give a certain effect; and that effect can be strong. Yet to the customer, the inability to comprehend each and every element that went into creating that ambiance gives it an additional sense of mystery, and that element of the unknown makes it all the more powerful.