Adventitious comes from Latin adventīcius, meaning "coming from outside," which, in turn, is from advenīre, "to arrive." The verb is the source of other English words, including advent, adventure, and …

ADVENTITIOUS definition: associated with something by chance rather than as an integral part; extrinsic. See examples of adventitious used in a sentence.

Their actions are more adventitious and unpredictable; they perceive and act under uncertainty.

Arising from an external cause or factor; not inherent: symmetry that was purely adventitious; adventitious circumstances that contributed to the plan's success.

Definition of 'adventitious' adventitious in American English (ˌædvɛnˈtɪʃəs , ˌædvənˈtɪʃəs ) adjective Origin: L adventicius, coming from abroad: see Advent

adventitious, adj. meanings, etymology, pronunciation and more in the Oxford English Dictionary

Arising from an external cause or factor; not inherent: symmetry that was purely adventitious; adventitious circumstances that contributed to the plan's success.