pertaining to fractions; comprising a part or the parts of a unit; constituting a fraction: fractional numbers.
comparatively small; inconsiderable or insignificant: The profit on the deal was fractional.
Chemistry. of or noting a process, as distillation, crystallization, or oxidation, by which the component substances of a mixture are separated according to differences in certain of their properties, as boiling point, critical temperature, or solubility.

Also frac·tion·ar·y [frak-shuh-ner-ee] /ˈfræk ʃəˌnɛr i/.

Origin of fractional

First recorded in 1665–75; fraction + -al1
Related formsfrac·tion·al·ly, adverbsub·frac·tion·al, adjectivesub·frac·tion·al·ly, adverbsub·frac·tion·ar·y, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for fractional

Contemporary Examples of fractional

Historical Examples of fractional

  • A fractional second of hesitation could not be permitted him.

    The Forest

    Stewart Edward White

  • For one fractional part of a second the stars and skies were blotted out.


    William Fitzgerald Jenkins

  • Small quantities are made by using a fractional part of this recipe.

    Checking the Waste

    Mary Huston Gregory

  • The resulting alcohol is separated by fractional distillation.

  • It is possible that they do get a second as it were fractional life in us.

    The Guardian Angel

    Oliver Wendell Holmes, Sr.

British Dictionary definitions for fractional


fractionary (ˈfrækʃənərI)


relating to, containing, or constituting one or more fractions
of or denoting a process in which components of a mixture are separated by exploiting differences in their physical properties, such as boiling points, solubility, etcfractional distillation; fractional crystallization
very small or insignificant
broken up; fragmented
Derived Formsfractionally, adverb
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for fractional

1670s, from fraction + -al (1).

Online Etymology Dictionary, © 2010 Douglas Harper