Lewis & Short

adventīcĭus (not -tĭus), a, um, adj. [advenio], that is present by coming, coming from abroad, foreign, strange (extrinsecus ad nos perveniens non nostrum, aut nostro labore paratum, Ern. Clav. Cic.; opp. proprius, innatus, insitus, etc.; in Cic. very freq., elsewhere rare).

  1. I. In gen.: genus (avium), Varr. R. R. 3, 5, 7 (cf. advena): Mithridates magnis adventiciis copiis juvabatur, Cic. Imp. Pomp. 9, 24; so, auxilium, id. Verr. 2, 4, 37: externus et adventicius tepor, id. N. D. 2, 10: externa atque adventicia visio, proceeding from the senses, id. Div. 2, 58, 128: doctrina transmarina et adventicia, id. de Or. 3, 33: dos, given by another than the father, Dig. 23, 3, 5.
  2. II. Esp.
    1. A. That is added to what is customary, or happens out of course, unusual, extraordinary: fructus, Liv. 8, 28; so, casus, Dig. 40, 9, 6.
    2. B. That is acquired without one’s own effort: adventicia pecunia, obtained, not from one’s own possessions, but by inheritance, usury, presents, etc., Cic. Inv. 2, 21; id. Rab. Post. 17: humor adventicius, rain, Varr. R. R. 1, 41, 3: adventiciae res, Sen. ad Helv. 5.
    3. C. That pertains to arrival (adventus): adventicia cena, a banquet given on one’s arrival, Suet. Vit. 13 (cf. adventorius).
      Adv. phrase: ex adventicio, from without, extrinsically: quidquid est hoc, quod circa nos ex adventicio fulget, liberi, honores, etc., Sen. Consol. ad Marc. 10.