saturated fat

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A fat, most often of animal origin, that is solid at room temperature and whose fatty acid chains cannot incorporate additional hydrogen atoms. An excess of these fats in the diet is thought to raise the cholesterol level in the bloodstream.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A fat or oil, from either animal or vegetable sources, containing a high proportion of saturated fatty acids; will typically be solid at room temperature; a diet high in saturated rather than unsaturated fats is thought to contribute to higher levels of cholesterol in the blood.