genitals; genitalia; reproductive organs
Medical and formal term for the external and internal reproductive organs. In everyday conversation, more colloquial terms are often used.
性器の清潔を保つことは健康に大切です。
Keeping the genitals clean is important for health.
He was arrested for exposing his genitals in the park.
The doctor performed an examination of the genitalia.
陰部 is a slightly softer, more euphemistic way to refer to the genital area, whereas 性器 is the direct medical term.
Compound of 性 (sei, 'sex, gender') and 器 (ki, 'organ, instrument').