Copulatory organ

A sex organ (also called a reproductive organ, primary sex organ, or primary sexual characteristic) is any anatomical part of the body in a complex organism that is involved in sexual reproduction and together constitute the reproductive system. The external and visible organs, in males and females, are the primary sex organs known as the genitals or genitalia. The internal organs are known as the secondary sex organs and are sometimes referred to as the internal genitalia. The characteristics that begin to appear during puberty, such as, in humans, pubic hair on both sexes and facial hair on the male, are known as secondary sex characteristics.

Mosses, ferns, and some similar plants have gametangia for reproductive organs, which are part of the gametophyte. The flowers of flowering plants produce pollen and egg cells, but the sex organs themselves are inside the gametophytes within the pollen and the ovule.Coniferous plants likewise produce their sexually reproductive structures within the gametophytes contained within the cones and pollen. The cones and pollen are not themselves sexual organs.

The Latin term genitalia, sometimes anglicized as genitals, is used to describe the externally visible sex organs, known as the primary sex organs: in male mammals, the penis and scrotum; and in female mammals, the clitoris and vulva.

The other, hidden sex organs are referred to as the secondary sex organs or internal genitalia. The most important of these are the gonads, a pair of sex organs, specifically the testes in the male or the ovaries in the female. Gonads are the true sex organs, generating reproductive gametes containing inheritable DNA. They also produce most of the primary hormones that affect sexual development, and regulate other sexual organs and sexually differentiated behaviors.

...
Wikipedia