adventitious

Adjective

adventitious (comparative more adventitious, superlative most adventitious)

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

   Synonyms:

   extrinsic, exogenous

2. Accidental, additional, appearing casually.
   • In a triad of verbs that admits nothing adventitious, Judah sees, takes, and lies with a woman; […]1981, Robert Alter, “A Literary Approach to the Bible”, in The Art of Biblical Narrative, page 6
   • The discovery of the art of making pottery was probably in all cases adventitious, the clay being first used for some other purpose.1895, Alfred C. Haddon, Evolution in Art, pages 101–102

   Synonyms:

   accidental, spontaneous, sporadic, incidental, coincidental, fortuitous, serendipitous, accidentary, by accident, by the by

3. Not congenital; acquired.

   Synonyms:

   acquired

4. Developing in an unusual place or from an unusual source.
   • 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;1985, R. M. T. Dahlgren, H. T. Clifford, P. F. Yeo, The Families of the Monocotyledons, page 101