In the Hanafi madhhab, a woman can either basically be a virgin or simply effectively so. An 'actual virgin' is a woman whose hymen ('A fold of tissue that partly covers the entrance to the vagina of a virgin') is still intact. An 'effective virgin' is a woman whom people consider still a virgin, regardless of whether she may have had sexual intercourse in the past without this being presently known about her. This is because virginity is something of great social weight in Islamic society, and for a past error (from which the woman has presumably repented) to affect her honor and future would be wrong.