The word logarithm means "ratio number," and was adopted by Napier after first using the expression artificial number. Briggs introduced the word mantissa, which is a late Latin term of Etruscan origin, originally meaning an "addition" or "makeweight," and which in the sixteenth century came to mean "appendix." The term characterislic was also suggested by Briggs and was used by Vlacq. It is curious that it was customary in early tables of common logarithms to print the characteristic as well as the mantissa, and that it was not until the eighteenth century that the present custom of printing only the mantissas was established.