Pronunciation: [ˈɛmbɹɪˌɒktənɪ] (IPA) 
Embryoctony, which is the process of cutting a developing embryo out of its yolk and into its own protective sac, is a word that may be difficult to spell for some. This word is pronounced /ɛmbrɪˈɒktəni/ according to the International Phonetic Alphabet. The spelling of "embryo" is straightforward, but the root word "octo" may throw some off as it refers to eight. However, in this case, it is used to mean "yolk," hence "octony."
Embryoctony is a rare biological phenomenon that refers to a reproductive strategy in which an animal's eggs are fertilized internally, develop within the body of the parent, and subsequently give birth to live offspring. This process is distinguished by the absence of external oviposition or laying of eggs, as seen in most oviparous species.
In the case of embryoctony, the developing embryos are nourished through a placenta-like structure known as a trophotaenia, which facilitates the transfer of nutrients from the parent to the developing offspring. This structure ensures that the embryos receive vital sustenance for their growth and development. As a result, the parent gives birth to fully-formed and independent young, rather than laying eggs for subsequent incubation or hatching.
Embryoctony is relatively uncommon and is observed in certain groups of animals, particularly certain species of sharks and rays, such as the hammerhead sharks and some species of skates. It is thought to have evolved as an adaptive strategy in response to specific ecological conditions or environmental constraints that favor the survival of offspring through internal gestation and live birth.
Overall, embryoctony is a reproductive strategy in which the internal fertilization, development, and subsequent live birth of offspring occur in an animal, bypassing the need for egg laying and external incubation.
Feticide, taking the life of the product of conception any time before birth.
A practical medical dictionary. By Stedman, Thomas Lathrop. Published 1920.
The word "embryoctony" is derived from two Greek roots: "embryo" and "ctonos".
1. "Embryo" (ἔμβρυον) in Greek means "unborn or unhatched offspring" and is derived from the verb "embryein" (ἐμβρύειν), which means "to be pregnant".
2. "Ctonos" or "Kyton" (κτών or κύτον) in Greek means "to kill, slay, or destroy". This root is typically associated with the act of killing or destroying embryos.
By combining these Greek roots, "embryoctony" describes the act of embryo destruction or the killing of unborn or unhatched offspring.
