A hematoma is a collectuion of blood under the skin, it is not just a bruise but may co-exist with a bruise. a black eye is usually a hematoma, and the black nail you get when you banfg your thumb with a hammer.
A vulval hematoma is a collection of blood in the vulva (the visible sex organs of the female). Commonly caused by a forceps delivery of a baby or an incorrectly sutured tear after delivery. Extremely uncomfortable for a week to ten days (ice packs help) but you end up as good as new.