E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
has reversed its original meaning (Latin, demereo, to merit, to deserve). Hence Plautus, Demertas dare laudas (to accord due praise); Ovid, Numna culta demeruisse; Livy, demerri beneficio civitatem. The de- is intensive, as in de-mand, describe, de-claim, etc.; not the privative deorsum, as in the word de-fame.