Virgin – A person that has never engaged in any sexual activity at all.
God used this word in its various forms 65 times in Scripture: 50 times to Israel in their Masoretic Text Old Testament; 7 times to Israel in their Koine Greek Old Testament (Matthew thru John); Once to the Body of Christ in the transition book of Acts; 6 times to the Body of Christ in the Gospel of Grace (Romans thru Philemon); and once to Israel’s Little Flock in their tribulation book of Revelation.
If the person has engaged in, or allowed, any sexual contact at all, they are not a virgin.
The Catholic Church has at least 2 additional definitions; “An unmarried or chaste woman noted for religious piety and having a position of reverence in the Church”, and “an unmarried woman who has taken a religious vow of chastity in order to dedicate herself totally to God”.
In creating these definitions, the Catholic Church also had to redefine “chaste”. Notice also that in their 2nd definition the unmarried woman need not be a virgin, she just has to take a vow of chastity.
In addition to the Christian additions to this word, secular additions have become abundant; basically to include anything that is lacking experience or being done for the first time.
See also Chaste, Christian, Damsel, Maid/Maiden, Mistress