mesophilous, mesophilic, mesophile, mesophily 1. Thriving under intermediate or moderate environmental conditions; sometimes restricted to conditions of moderate moisture, or to moderate temperature. 2. A reference to micro-organisms having an optimum for growth between 20 and 45 degrees Centigrade. 3. Organisms, such as bacteria, that thrive at hu... Found on http://www.wordinfo.info/words/index/info/view_unit/1299/3