sclerotin
/ˈsklɪərətɪn
/ /ˈsklɛrətɪn/noun [mass noun] Biochemistry
A structural protein which forms the cuticles of insects and is hardened and darkened by a natural tanning process in which protein chains are cross-linked by quinone groups.
Origin
1940s: from sclero- 'hardened', on the pattern of such words as keratin.