Virilization

[Sarah]

Virilization is the development of exaggerated masculine characteristics, usually in women, often as a result of the adrenal glands overproducing androgens (male sex steroid hormones such as testosterone ).

Virilization is caused by excess production of androgens usually because of a tumor in or enlargement of an adrenal gland or a tumor in an ovary or abnormal hormone production by the ovaries.
Symptoms include excess facial and body hair, baldness, acne, deepening of the voice, increased muscularity, and an increased sex drive.
The body changes make it easy for doctors to recognize virilization, and the dexamethasone suppression test can help doctors determine the cause.
The adrenal gland that contains the tumor is surgically removed, although sometimes drugs can reduce the excess hormone production.

(See also Overview of the Adrenal Glands.)
The most common cause of virilization caused by adrenal sex hormones is an

Enlargement of the hormone-producing portions of the adrenal cortex (adrenal hyperplasia)

Other causes include

A hormone-producing tumor (adenoma or cancer) in the adrenal gland
A cancer outside the adrenal gland that produces adrenal androgens
Large amounts of androgen pills or injections (anabolic steroids) taken to increase muscle bulk
An abnormality in an enzyme (protein) in the adrenal glands that is present from birth

Cancers outside the adrenal glands that produce androgens are likely to be tumors of the ovaries. Enlargement of the ovaries due to certain types of ovarian cysts may cause virilization, but such cases are almost always mild. Occasionally, overactivity of androgen secretion by the ovaries may occur in later life.
An enzyme abnormality in the adrenal glands is often diagnosed in childhood or adolescence and is termed congenital adrenal hyperplasia.

[Vania]

The development of male physical characteristics (such as muscle bulk, body hair, and deep voice) in a female or precociously in a boy, typically as a result of excess androgen production.

[Zipporah Schumaker]

When a [female bodybuilder] who is taking a testosterone based Performance Enhancing Drug (PED) begins to develop masculine traits as a result of [hormone imbalance]. Typically consists of one or several of the following:
Deepening voice
Increased Body Hair Growth
Enlargement of the Clit
Heightened Libido
Mood shifts/Personality Changes
These effects may fade upon coming off cycle, or they may linger for some time. In some sever cases, it can lead to [infertility].