[eg-zap-tey-shuh n, ek-sap-]
noun Biology.
  1. a process in which a feature acquires a function that was not acquired through natural selection.
  2. a feature having a function for which it was not originally adapted or selected.
  3. a morphological or physiological feature that predisposes an organism to adapt to a different environment or lifestyle.
  4. predisposition toward adaptation.
Related formsex·apt·ed, adjectiveex·ap·tive [eg-zap-tiv, ig-, ek-sap-] /ɛgˈzæp tɪv, ɪg-, ɛkˈsæp-/, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018