Main Entry: ad·ven·ti·tious

Pronunciation: \-əs\

Function: adjective

1 a : arising sporadically or in other than the usual location <an adventitious part in embryonic development> b : occurring spontaneously or accidentally in a country or region to which it is not native <an adventitious insect>
2 : adventitial
3 : not congenital <adventitious deafness>

—ad·ven·ti·tious·ly adverb