Definition of neotenize in US English:

neotenize

(also neotenise)

verb

  • with object To cause to become neotenic; to breed (a domestic animal) to retain juvenile characteristics in adulthood. Also: to endow (a person or animal) with immature features or attributes; to make juvenile in appearance or behaviour.

Origin

1970s; earliest use found in Desmond Morris (b. 1928). From neoten- + -ize.