Mormo (Greek: Μορμώ, Mormō) was a female spirit in Greek folklore, whose name was invoked by mothers and nurses to frighten children to keep them from misbehaving.
The term mormolyce /mɔːrˈmɒlɪˌsiː/ (μορμολύκη; pl. mormolykeia μορμολύκεια), also spelt mormolyceum /mɔːrˌmɒlɪˈsiːəm/ (μορμολυκεῖον mormolukeîon), is considered equivalent.