Superfetations

Part of speech: noun

Definitions

1. Instances of a second conception occurring while a pregnancy is already underway, producing fetuses of different developmental ages ; additional layers or growths added on top of something already formed
2. Cases where a new embryo is conceived during an ongoing pregnancy so that offspring of differing ages develop together ; unnecessary accretions or extra additions piled onto an existing structure or work
3. Biological events in which a fresh conception happens in a female already carrying young ; surplus embellishments or excessive layers accumulated over something that already stands

Etymology: Superfetation is the medical and biological term for the conception of a second embryo while an earlier pregnancy is already underway, so that two litters or broods of different ages develop together. The word comes from Latin "superfetare," meaning "to conceive while pregnant," built from "super-," meaning "over" or "above," and "fetus," meaning "offspring" or "pregnancy." The literal sense is thus something like "conceiving on top of," which describes the physical situation exactly. The plural "superfetations" is simply the form used when discussing more than one instance of this phenomenon, often in the context of animal reproduction, where it has been observed in some species.

Synonyms: superimpregnation