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trans fatty acid

An unsaturated fatty acid produced by the partial hydrogenation of vegetable oils. Trans fatty acids were once commonly used in margarines, shortenings, and fried foods, but an excess of these fats in the diet is associated with high LDL cholesterol levels, low HDL cholesterol levels, and an increased risk of coronary heart disease, so they have been banned from use in most food products in the United States.

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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