How do you spell Adventitious

Available Definitions:
1)  a. - Added extrinsically; not essentially inherent; accidental or causal; additional; supervenient; foreign.
2)  a. - Out of the proper or usual place; as, adventitious buds or roots.
3)  a. - Accidentally or sparingly spontaneous in a country or district; not fully naturalized; adventive; -- applied to foreign plants.
4)  a. - Acquired, as diseases; accidental.