Definitions

1. adjective

growing or occurring in a place not as a normal part of its environment; extrinsic or adventive.

“The adventitious moss found on the old stone wall had adapted to the local climate.”

2. noun

an adventitious growth or structure; especially a growth that is not normally present but appears in response to injury or disease.

“The doctor examined the patient’s adventitious growth on her skin.”

3. adverb

in an adventitious manner; in an extrinsic way.

“The plant grew adventitiously in the cracks of the pavement.”