[soo-per-floo-id] 
Physics.| 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. |
| 2. | of or pertaining to a superfluid. |
superfluid (s 'pər-fl'ĭd) Pronunciation Key
A fluid, such as liquid helium, that flows with little or no friction at temperatures close to absolute zero. |
pərˈflu