Alz?hei?mer’s disease` (??lts ha? m?rz, ?ælts-, ??lts-) n. a common form of dementia of unknown cause, usu. beginning in late middle age, characterized by progressive memory loss and mental deterioration associated with brain damage. [after Alois Alzheimer (1864?1915), German neurologist, who described it in 1907] Random House Kernerman Webster’s College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.