ge·oph·a·gy (j?-?f??-j?)n. The eating of earthy substances, such as clay or chalk, practiced among various peoples as a custom or for dietary or subsistence reasons.ge·oph?a·gism n.ge·oph?a·gist n.American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.geophagy (d????f?d??) , geophagia or geophagismn1. (Anthropology & Ethnology) the practice of eating earth, clay, chalk, etc, found in some primitive tribes2. (Zoology) zoology the habit of some animals, esp earthworms, of eating soil ge?ophagist n geophagous adjCollins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014ge?oph?a?gy (d?i??f ? d?i) also ge?o?pha?gia (?d?i ??fe? d??, -d?i ?) n. the practice of eating earthy matter, esp. clay or chalk, as in famine-stricken areas. [1840?50] ge?oph?a?gous (-g?s) adj. Random House Kernerman Webster’s College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.geophagism, geophagy, geophagiathe eating of earthy matter, especially clay or chalk. ? geophagist, n. ? geophagous, adj.See also: Earth-Ologies & -Isms. Copyright 2008 The Gale Group, Inc. All rights reserved.