I find this interesting. Based on this then, it seems that there is a difference between virgin and purity in their definitions. Virginity seems like an externally gained quality derived from a woman's experience and wisdom due to being married. Whereas, purity/chaste(this seems maybe the better word) seems to be the intrinsic quality of never having been sexually penetrated. Thus, a woman who has been sexually active but never married may be said to be a virgin but impure(not to be mistaken as najasah).