Definition of mortalness in English:

mortalness

Pronunciation /ˈmɔːtəlnəs/ /ˈmɔːt(ə)lnəs/

noun

rare
  • The quality of being mortal.

Origin

Mid 16th century; earliest use found in John Palsgrave (d. 1554), teacher and scholar of languages. From mortal + -ness.