beta-sitosterol
noun
beta-si·tos·ter·ol
variants:
also β-sitosterol \ -sī-ˈtäs-tə-ˌrȯl, -ˌrōl 
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Medical Definition of beta-sitosterol
: a sterol widespread in plant products (as wheat germ, soybeans, and corn oil) that is used in dietary supplements and is held to lower cholesterol levels and relieve symptoms of benign prostatic hyperplasia