Virginity is the noun for the state of never having had sex. It is the abstract word behind the adjective: a virgin *has* virginity, and when a person first has sex, English says they "lose their virginity." That set phrase is by far the most common way you will meet the word — "lose" and "virginity" travel together, and the fixed opposite, oddly, does not exist (nobody "gains" virginity).

The register sits in an unusual place. It is a plain, printable word — newspapers, health classes, and novels all use it without fuss — but the topic itself is private, so people lower their voices or reach for something vaguer in ordinary conversation. It is not rude, and it is not clinical either.

Two things worth knowing. First, it applies to any gender; the older habit of using it mainly about women is a habit of the culture, not a rule of the word. Second, English stretches it as a joke or a figure of speech to mean "the first time you do anything": people write about losing their "political virginity" at a first election, or a climber's "virginity" on a mountain. That stretched use is deliberate and slightly cheeky — the reader is meant to notice.

In religious writing, particularly Catholic writing, virginity can mean a chosen lifelong state, treated as something valuable rather than something merely not yet lost.