nuclein
/ˈnjuːklɪɪn/(also nucleïn) Biochemistry
noun
1Originally: protein that is rich in phosphorus, especially nucleoprotein or phosphoprotein. Later: specifically nucleohistone or nucleoprotamine.
2= nuclein base. rare. disused.
Origin
Late 19th century; earliest use found in Journal of the Chemical Society. From German Nuclein from Nucleus (now usually Nukleus) nucleus + -in.