Main Entry:

al·ka·loid

Pronunciation:

\ˈal-kə-ˌlȯid\

Function:

noun

Date:

circa 1831

: any of numerous usually colorless, complex, and bitter organic bases (as morphine or caffeine) containing nitrogen and usually oxygen that occur especially in seed plants and are typically physiologically active

— al·ka·loi·dal \ˌal-kə-ˈlȯi-d^əl\ adjective