The word ‘dementia’ first appeared in the record of mankind in around 600 A.D. Saint Isidore (560–636 A.D.), the archbishop of Seville, used the term ‘dementia’ for the first time in his book, ‘Etymologies’. The term has its origin in Latin, and is formed from the prefix ‘de’, which means a deprivation or loss; root ‘ment’, which means mind; and suffix ‘ia’, which indicates a state. In short, dementia refers to ‘a state out of mind’.