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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