Adventitious vs Undefined - What's the difference?

As adjectives the difference between adventitious and undefined

is that adventitious is from an external source; not innate or inherent, foreign while undefined is lacking a definition or value.

(en adjective)

From an external source; not innate or inherent, foreign.

Accidental, additional, appearing casually.

* 2002 , , The Great Nation , Penguin 2003, p. 30:

The adventitious disappearance of those nearer the the throne than the duke had, moreover, set tongues awagging.

(genetics, medicine) Not congenital; acquired.

(biology) Developing in an unusual place or from an unusual source.

* 1985 , , H. T. Clifford, & P. F. Yeo, The Families of the Monocotyledons , page 101

The Velloziaceae have evolved a woody stem which is covered with a layer of adventitious roots mingled with the fibres of the old leaf sheaths;

* (from an external source) extrinsic * accidental, spontaneous, sporadic * (not congenital) acquired

* adventitiously * adventitiousness

(wikipedia undefined) (-)

Lacking a definition or value.

(mathematics, computing) That does not have a meaning and is thus not assigned an interpretation.

The result of division by zero is undefined .

* defined