Definition of neoteny in US English:

neoteny

noun

Zoology
  • 1The retention of juvenile features in the adult animal.

    Also called pedomorphosis
    • ‘Among early codiacrinids adaptive forms evolved initially through both neoteny and progenesis.’
    • ‘Some species (for example, the axolotl) display neoteny - that is, the larval features persist into sexual maturity.’
    • ‘This combination of characters is best interpreted as evolution through neoteny.’
    • ‘In fact Neo, as he has been named, suffers from a condition known as neoteny, where juvenile characteristics, like gills, are retained into adulthood.’
    • ‘This is a classic example of an evolutionary phenomenon known as neoteny - the retention of larval or juvenile features in mature adults.’
    1. 1.1 The sexual maturity of an animal while it is still in a mainly larval state, as in the axolotl.
      Also called pedogenesis
      • ‘The acquisition of sexual maturity by an animal while still in the larval stage is a process that goes under the name neoteny.’
      • ‘Facultative neoteny also occurs in some species of true salamanders.’

Origin

Late 19th century: from German Neotenie, from Greek neos ‘new’ (in the sense ‘juvenile’) + teinein ‘extend’.

Pronunciation

neoteny

/niˈɑt(ə)ni//nēˈät(ə)nē/