Grattage. a method of drawing by scratching paper or cardboard that has been covered with india ink with a pen or a sharp instrument. The grattage process is reminiscent of scraping an oiled surface in lithography.rattage. a method of drawing by scratching paper or cardboard that has been covered with india ink with a pen or a sharp instrument. The grattage process is reminiscent of scraping an oiled surface in lithography.
3. (Zoology) of or relating to the surface of an animal, such as a jellyfish, on which the mouth is situated. 4. (Medicine) denoting a drug to be taken by mouth Compare parenteral: an oral contraceptive.
Enamel: n. Anatomy - The hard, calcareous substance covering the exposed portion of a tooth . In Megalodon teeth this is the top layer of material on the crown of the tooth that does not fossilize. The bourlette is also enamel. The crown and bourlette enamel is the only original part of the tooth left after fossilization.