- dementia
- 1806, L. noun of state from dementem, from dementer (see dement). It existed earlier in an anglicized form, demency (1520s), from Fr. démence. Dementia præcox is a Mod.L. form recorded from 1899 in Eng., 1891 in Ger., from Fr. démence précoce (1857). See precocious.