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herd immunity - n. herd immunity is a form of protection from infectious disease when a large percentage of a population has become immune to an infection, whether through vaccination or previous infections, thereby reducing the likelihood of infection for individuals who lack immunity.
ambiguity - n. something that does not have a single clear meaning
appropriate - adj. right or suited for some purpose or situation
bioethics - n. the study of the ethical issues emerging from advances in biology and medicine.
transfer - v. move to another school
