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Pronunciation: par'a-sit


  1. An organism that lives on or in another and draws its nourishment therefrom.
  2. In the case of a fetal inclusion or conjoined twins, the usually incomplete twin that derives its support from the more nearly normal autosite.

[G. parasitos, a guest, fr. para, beside, + sitos, food]

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© Copyright 2018 Wolters Kluwer. All Rights Reserved. Review Date: Sep 19, 2016.