pregnane
/ˈprɛɡneɪn/Chemistry
noun
A tetracyclic saturated hydrocarbon, C21H36, which has two stereoisomeric forms and whose molecule is the framework of those of a group of steroids, including progesterone and pregnanediol; specifically the 5β-isomer.
Origin
1930s; earliest use found in Annual Reports Progress Chemistry. From German Pregnan from Pregnan- (in Pregnandiol), with ending probably reanalysed as -an.