(plural lusus naturæ or lusûs naturæ)
- (historical, originally) A supposed capricious act of Nature regarded as the cause and origin of marked phænotypic anomalies in a given organism.
- (chiefly in this concrete sense) An organism exhibiting marked phænotypic deviation from the norm, seeming to be the result of sportive design.
From Latin lūsus nātūræ (“sport of Nature”), from lūsus (“playing”, “sport”) + nātūræ (“of Nature”), genitive singular form of nātūra (“Nature”).
From Latin lūsūs nātūræ (“sports of Nature”), from lūsūs (“playings”, “sports”), nominative plural form of lūsus + nātūræ.