a chemical derivative, CHO, of cortisone, but with fewer side effects, used in the treatment of arthritis and certain allergic and inflammatory disorders
See prednisone in American Heritage Dictionary 4
(prĕdˈnĭ-sōnˌ,-zōnˌ)
noun
A synthetic steroid, C21H26O5, similar to cortisone that is used as an antiallergic and immunosuppressive drug and as an anti-inflammatory agent in the treatment of rheumatoid arthritis.