Definition of ontogenesis in US English:



  • The development of an individual organism or anatomical or behavioral feature from the earliest stage to maturity.

    Compare with phylogenesis
    • ‘Shepard proposes that humans go through eight stages of ontogenesis in their first twenty years of life.’
    • ‘The concepts of penetrance and expressivity and also of the systemic regulation of the formation of phenotypic traits - the foundation of phenogenetics and the genetics of ontogenesis.’
    • ‘Since this field of biogenesis is not available to us, we shall do as biologists do and turn to ontogenesis.’
    • ‘Ductal plate malformation results from persistence or absence of remodeling of the embryonic ductal plate during ontogenesis.’
    • ‘Some degree of variation seems attributable to ontogenesis, as large morphological distances are observed between young and adult specimens.’


Late 19th century: from Greek ōn, ont- ‘being’ + genesis ‘birth’.