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.
2. (tr) to prevent the passage of. 3. (Chemistry) (tr) chem (of a solid) to incorporate (a substance) by absorption or adsorption. 4. (Physical Geography) meteorol to form or cause to form an occluded front. 5. (Dentistry) dentistry to produce or cause to produce occlusion, as in chewing.