cul-de-sac In anatomy, a blind pouch or cavity that is closed at one end. The term cul-de-sac is used specifically to refer to the rectouterine pouch (the pouch of Douglas), an extension of the peritoneal cavity between the rectum and back wall of the uterus.
cuboid bone The cube-shaped outer bone in the instep of the foot. The cuboid bone has a joint in back that allows it to articulate posteriorly with the calcaneus (the heel bone). It also has a joint in the front that permits it to articulate anteriorly with the fourth and fifth metatarsals (the bones just…
CTS Carpal tunnel syndrome.
CTL Cytotoxic T lymphocytes. See T lymphocyte, cytotoxic.
CT scan See CAT scan.
CSF 1 Cerebrospinal fluid. 2 Colony-stimulating factor.
C-section See caesarean section.
cryptorchidism A condition in which one or both testicles fail to move from the abdomen, where they develop before birth, down into the scrotum. Boys who have had cryptorchidism that was not corrected in early childhood are at increased risk for developing cancer of the testicles. Also known as undescended testicles.
crypt In anatomy, variously a blind alley, a tube with no exit, a depression, or a pit in an otherwise fairly flat surface. For example, the tonsillar crypts are little pitlike depressions in the tonsils.
cryosurgery Treatment performed with an instrument that freezes and destroys abnormal tissue.
cryoprotectant A chemical component of a freezing solution used in cryopreservation to help protect what is being frozen from freeze damage. The chemical glycerol, for example, is commonly used as a cryoprotectant to protect frozen red blood cells.
cryopreservation The process of cooling and storing cells, tissues, or organs at very low temperatures to maintain their viability. For example, the technology of cooling and storing cells at a temperature below the freezing point (–196° C) permits high rates of survivability of the cells upon thawing.