What does chorioallantoic mean?
"Chorioallantoic" is a technical adjective used in embryology and biomedical research to describe anything relating to the chorioallantois — the highly vascular membrane formed when two extraembryonic structures, the chorion and the allantois, fuse during development in birds, reptiles, and certain mammals. In these animals, the chorioallantoic membrane lies just beneath the eggshell and serves as the embryo's main organ of gas exchange, functioning much like a lung. The adjective appears overwhelmingly in scientific contexts, most famously in the phrase "chorioallantoic membrane," often shortened to CAM, which has long served as a standard substrate for growing viruses and for studying angiogenesis, wound healing, and tumor biology. Though rare outside specialist literature, the word is a precise and indispensable term for anyone reading research in developmental biology or virology.
adjectiveRelating to or involving the chorioallantois, the vascular membrane formed by the fusion of the chorion and allantois in the embryos of birds, reptiles, and some mammals.
- Of or relating to the chorioallantois, the combined chorion–allantois membrane in avian, reptilian, and some mammalian embryos.
"Viral growth was measured on the chorioallantoic membrane of fertilized hen eggs."
"The vaccine strain was propagated in eggs by inoculation onto the chorioallantoic membrane."
"Researchers observed dense blood vessel formation across the chorioallantoic tissue during mid-incubation."
The chorioallantoic membrane of a chicken egg became one of science's most useful tools — it's how researchers grew viruses and even tested chemicals for corrosion without touching a living animal.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of chorioallantoic
Chorioallantoic derives from two Greek roots joined through anatomical Latin: 'chorion,' from Greek 'khorion' meaning a membrane or skin, and 'allantois,' from 'allas' meaning sausage, so named because that embryonic sac resembles a sausage shape. The term arose in nineteenth-century comparative anatomy as scientists described the fusion of these two membranes in amniote embryos. Its roots also underlie related anatomical terms such as chorion, chorionic, and allantoic.
How chorioallantoic is actually used
Strictly a technical term used in embryology, developmental biology, virology, and veterinary medicine. It almost never appears outside scientific writing and is typically encountered as part of the fixed phrase 'chorioallantoic membrane' (often abbreviated CAM).
Easily confused with chorioallantoic
Chorionic refers to the chorion alone, while chorioallantoic refers to the fused structure formed by the chorion and the allantois together.