|an obscure term ostensibly referring to a lung disease caused by silica dust, sometimes cited as one of the longest words in the English language.|
|a white, crystalline, water-insoluble, powerful high explosive, C3H6N6O6, used chiefly in bombs and shells.|
polyembryony pol·y·em·bry·o·ny (pŏl'ē-ěm'brē-ə-nē, -ěm-brī'-)
Development of more than one embryo from a single egg or ovule.
|polyembryony (pŏl'ē-ěm'brē-ə-nē, -ěm-brī'-) Pronunciation Key
Development from a single fertilized egg cell or, in plants, from a single ovule. In human beings, identical twins are the result of polyembryony. In gymnosperm plants, polyembryony involves the fertilization of more than one egg, though usually only one embryo survives in the ovule.
a condition in which two or more embryos develop from a single fertilized egg, forming what in humans is known as identical twins. A common phenomenon in many plant and animal species, polyembryony occurs regularly in the nine-banded armadillo, which usually gives birth to four identical young. Striking examples may be found among parasitic insects of the order Hymenoptera; Copidosoma truncatellum, a parasite of certain cutworms, lays a single egg in the body of the host worm from which may develop as many as 2,000 individuals.
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