The term ABNORMAL SAC is composed of four crossword solutions: CYST (4 letters), AMNION (6 letters), LEMAY (5 letters), and OVI (3 letters). A CYST is a closed sac-like structure that can contain fluid, gas, or semi-solid material. An AMNION is a thin membrane that surrounds and protects the embryo in the uterus. Lemay is a type of abnormal sac that forms in the uterus during pregnancy. Ovi is a medical term for an egg or ovum. Together, these four terms describe an abnormal sac that can form in the uterus during pregnancy.