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

Until now, however, no experiment had clearly shown a superfluid naturally transforming into a supersolid.

From Science Daily • Feb. 5, 2026

The breaking of the B-L symmetry produced strings that behave like magnetic flux tubes, while the PQ symmetry created superfluid vortices that carry no magnetic flux.

From Science Daily • Dec. 7, 2025

The team constructed a bespoke cryogenic system capable of containing several litres of superfluid helium at temperatures lower than -271 °C. At this temperature liquid helium acquires unusual quantum properties.

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