1. Mathematics An expression that indicates the quotient of two quantities, such as 1/3 .
2. A disconnected piece; a fragment.
3. A small part; a bit: moved a fraction of a step.
4. A chemical component separated by fractionation.
[Middle English fraccioun, a breaking, from Anglo-Norman, from Late Latin frāctiō, frāctiōn-, from Latin frāctus, past participle of frangere, to break; see bhreg- in the Appendix of Indo-European roots.]
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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:
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.