Cenozoic Era   Origin of the Term Cenozoic (Cainozoic) [1840]. Established by John Phillips in 1840 (with further discussion in 1841) as broad, interpretive categories of rock units based on overall fossil content. Reflected middle and late animal life. Note, Cainozoic (actually Kainozoic in 1840, re-spelled Cainozoic in 1841) is the preferred usage in Great Britain. Stanley M. Awramik