amnesia Look up amnesia at Dictionary.com
"loss of memory," 1786, coined from Gk. amnesia "forgetfulness," from a-, privative prefix, "not" + mimneskesthai "to recall, cause to remember," a reduplicated form related to Gk. mnemnon "mindful," mneme "memory," mnasthai "to remember;" from PIE base *men- "to think, remember" (see mind (n.)).