An acidophile's an inorganic particle or living organism (or part thereof) that tends toward acidic conditions or acids. Cf. "Acidophobe". Specifically, it can refer to the following:* Acidophile (histology) Acidophile (organisms) Acidophiles live in environments that're below a ph level of 2.0 (very acidic). The PH scale goes from 1 - 14, 1 being very acidic, 7 being neutral, and 14 being very basic.… (More on Acidophile)