acidophil /as″idōfil, əsid″əfil/ [L, acidus, acid + Gk, philein, to love] , 1. a particular staining pattern of cells and tissues when using haematoxylin and eosin stains. Specifically, a cell or cell constituent with an affinity for acid dyes. The most common such dye is eosin, which stains acidophilic organisms red and is the source of the related term eosinophilic. See also eosinophilic. 2. an organism that thrives in an acid medium. −acidophilic, adj.
