fruc·tose (fr?k?t?s?, fro?ok?-)n. A very sweet monosaccharide sugar, C6H12O6, occurring in many fruits and in honey, and used as a preservative for foodstuffs and as an intravenous nutrient. Also called fruit sugar, levulose.[Latin fr?ctus, fruit; see fruit + -ose.]American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.fructose (?fr?kt??s; -t??z; ?fr?k-) n (Elements & Compounds) a white crystalline water-soluble sugar occurring in honey and many fruits. Formula: C6H12O6. Also called: laevulose or fruit sugar [C19: from Latin fr?ctus fruit + -ose2]Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014fruc?tose (?fr?k to?s, ?fr?k-, ?fruk-) n. a crystalline, water-soluble, levorotatory ketose sugar, C6H12O6, sweeter than sucrose, occurring in invert sugar, honey, and many fruits: chiefly used in foodstuffs. [1860?65;