Noun
Oneness of origin; esp. (Biol.), development of all beings in the universe from a single cell; -- opposed to polygenesis. Called also monism.
That form of reproduction which requires but one parent, as in reproduction by fission or in the formation of buds, etc., which drop off and form new individuals; asexual reproduction.
The direct development of an embryo, without metamorphosis, into an organism similar to the parent organism; -- opposed to metagenesis.
Source: Webster's dictionaryMonogenesis was dismissed by many linguists in the late 19th and early 20th centuries, when the doctrine of the polygenesis of the human races and their languages was widely popular (e.g. Saussure 1986/1916:190). Source: Internet