What's the "een" in Halloween?
early 15c., from Latin contaminationem (nominative contaminatio), noun of action from past participle stem of contaminare (see contaminate). Figurative sense is from c.1620; specifically of radioactivity from 1913.
contamination con·tam·i·na·tion (kən-tām'ə-nā'shən)
The act or process of rendering something harmful or unsuitable.
The presence of extraneous, especially infectious, material that renders a substance or preparation impure or harmful.
in manuscript tradition, a blending whereby a single manuscript contains readings originating from different sources or different lines of tradition. In literature, contamination refers to a blending of legends or stories that results in new combinations of incident or in modifications of plot.