antiandrogen

n. agent that inhibits activity of a male sex hormone by blocking the hormone's receptors

An antiandrogen, or androgen antagonist, is any of a group of hormone receptor antagonist compounds that are capable of preventing or inhibiting the biologic effects of androgens, male sex hormones, on normally responsive tissues in the body (see androgen insensitivity syndrome). Antiandrogens usually work by blocking the appropriate receptors, competing for binding sites on the cell's surface, obstructing the androgens' pathway.
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Antiandrogen /an·ti·an·dro·gen/ any substance capable of inhibiting the biological effects of androgens. an·ti·an·dro·gen n. [more]Antiandrogen - Community and Resources

[an-tee-AN-dro-jen]
A drug used to block the production or interfere with the action of male sex hormones. 

Treatment with drugs used to block production or interfere with the action of male sex hormones.