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  • coming from another source; arising or occurring sporadically or in other than the usual location [adj ADVENTITIOUSLY]
  • Happening or carried on according to chance rather than design or inherent nature
  • Coming from outside; not native
  • Formed accidentally or in an unusual anatomical position
  • means coming from another source, and it is used in formal writing.
  • (of a root) Growing directly from the stem or other upper part of a plant