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fluid ounce

noun

a measure of capacity equal to 1/16 (0.0625) pint (29.6 milliliters) in the U.S., and equal to 1/20 (0.05) of an imperial pint (28.4 milliliters) in Great Britain. Abbreviation: fl. oz; Symbol: f

Origin of fluid ounce

First recorded in 1880–85
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for fluid ounce

fluid ounce

noun

a unit of capacity equal to the volume of one avoirdupois ounce of distilled water at 62°F: there are twenty fluid ounces in an Imperial pint and sixteen in a US pint
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
fluid ounce in Medicine

fluid ounce

n.

A unit of volume or capacity equal to 8 fluid drams or 29.57 milliliters.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
fluid ounce in Science

fluid ounce

A unit of liquid volume or capacity in the US Customary System equal to 116 of a pint (29.57 milliliters). See Table at measurement.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.