The term 'Female Monster of Greek Myth' can be summarized by the crossword solution 'Lamia' (5 letters). Lamia was a female monster in Greek mythology, described as having a human upper body and a serpentine lower body. She was said to have been a queen of Libya who was cursed by Hera and transformed into a monster. Lamia was known for her ability to shape-shift and her voracious appetite for children.