an instrument for measuring the rate of flow of a liquid, consisting of a tapered vertical tube in which a small float is forced upward until its weight balances the fluid force.
Origin of rotameter
partial translation of German Rotamesser (1911), equivalent to Rota(tion) rotation + Messer measurer, meter
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
trademark a device used for measuring the flow of a fluid. It consists of a small float supported in a tapering glass by the flow of the fluid, the height of the float indicating the rate of flow
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