steroid

Any of a group of cyclic, unsaturated alcohols (lipids without fatty acid components), which, like sterols, have a complex molecular structure consisting of four carbon rings. Steroids include the sex hormones, such as testosterone, the corticosteroid hormones produced by the adrenal gland, bile acids, and cholesterol.

The term is commonly used to refer to anabolic steroid. In medicine, synthetic steroids are used to treat a wide range of conditions.

Steroids are also found in plants. The most widespread are the brassinosteroids, necessary for normal plant growth.