Synonyms of adventitious in English:

adventitious


See definition of adventitious

adjective

1‘he felt that the conversation was not entirely adventitious’

SYNONYMS
unplanned, unpremeditated, accidental, unintentional, unintended, unexpected, unforeseen, involuntary, chance, fortuitous, serendipitous, coincidental, casual, random, fluky, unlooked-for, unhoped-for, not bargained for, out of the blue, without warning
rare aleatory
ANTONYMS

planned

2‘some rural parishes recorded high adventitious populations’

SYNONYMS
foreign, alien, non-native, outside, external, extraneous, extrinsic
ANTONYMS

native, indigenous