Comeday morm

• Monday morn → generally regarded as the beginning of the week in Ireland

• come Monday morn

• Comeday morm and → Come the morning

• someday

• comedy → contrasted with tragoady three lines below

• mormō (μορμω): (Greek) bugbear, spectre, she-monster → Lilith, a female night demon of Mesopotamian mythology; according to some accounts she was Adam's first wife and the mother of Cain → contrasted with Eve in the next line
  • Wikipedia
  • Third Census of Finnegans Wake