superfluid

American  

[soo-per-floo-id] / ˌsu pərˈflu ɪd /

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.

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adjective

1. of or relating to a superfluid.

superfluid British  

/ ˌsuːpəˈfluːɪd /

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

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adjective

1. being or relating to a superfluid

superfluid Scientific  

/ so̅o̅′pər-flo̅o̅′ĭd /

1. A fluid, such as liquid helium, that flows with little or no friction at temperatures close to absolute zero.

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Other Word Forms

• superfluidity noun

Etymology

Origin of superfluid

First recorded in 1940–45; super- + fluid

Example Sentences

Physicists have long wondered what would happen if a superfluid were cooled even further.

From Science Daily • Feb. 5, 2026

In bilayer graphene, the excitonic superfluid and likely supersolid only appear under strong magnetic fields.

From Science Daily • Feb. 5, 2026

In turn, this coupling allows the PQ superfluid vortex to pump electric charge into the B-L flux tube and oppose the tension that would normally cause the loop to shrink and snap.

From Science Daily • Dec. 7, 2025

They have created a giant swirling vortex within superfluid helium that is chilled to the lowest possible temperatures.

From Science Daily • Mar. 20, 2024

In his most noteworthy calculation, he corrected a longstanding theory of superfluid helium established by Lev Landau, winner of a Nobel Prize in Physics.

From New York Times • Mar. 19, 2024