Definition of grimalkin in English:

grimalkin

noun

Archaic
  • 1A cat (used especially in reference to its characteristically feline qualities)

    • ‘She's written six paranormal romances about love complicated by grimalkins, witches, Druids, mermaids, and even mad scientists.’
    1. 1.1A spiteful old woman.

Origin

Late 16th century: from gray + Malkin (nickname for the given name Matilda).

Pronunciation:

grimalkin

/ɡrəˈmalkən/