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superfluid

[soo-per-floo-id]Physics.
noun
  1. a fluid that exhibits frictionless flow, very high heat conductivity, and other unusual physical properties, helium below 2.186 K being the only known example.
adjective
  1. of or relating to a superfluid.

Origin of superfluid

First recorded in 1940–45; super- + fluid
Related formssu·per·flu·id·i·ty, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for superfluid

superfluid

noun
  1. physics a fluid in a state characterized by a very low viscosity, high thermal conductivity, high capillarity, etc. The only known example is that of liquid helium at temperatures close to absolute zero
adjective
  1. being or relating to a superfluid
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
superfluid in Science

superfluid

[sōō′pər-flōō′ĭd]
  1. A fluid, such as liquid helium, that flows with little or no friction at temperatures close to absolute zero.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.