adventitious
adventitious (ad`ven*tish"us) , adjective
[Latin adventitius.]
1.
Added extrinsically; not essentially inherent.
To things of great dimensions, if we annex an adventitious idea of terror, they become without comparison greater.
2.
(Nat. Hist.) Out of the proper or usual place; as, adventitious buds or roots.
3.
(Botany) Accidentally or sparingly spontaneous in a country or district; not fully naturalized; adventive; -- applied to foreign plants.
4.
(Medicine) Acquired, as diseases; not hereditary. — AS
5.
(Medicine) Occurring in an unusual place or arising from an external source. — Stedman 25