What does impeller mean?
An impeller is a rotating part of a pump, turbine, or similar machine that gives energy to a liquid or gas and sends it through the equipment. Its blades or vanes move as the shaft turns, creating pressure, flow, or suction. In a centrifugal pump, for example, the impeller draws fluid into its centre and directs it outward, increasing its velocity and pressure. The word is mainly used in engineering and industrial contexts, though it can also describe a device whose general purpose is to impart motion to a fluid. It is related in origin to impel, meaning to drive or urge forward, and to words such as impulse and impetus. Although an impeller and a propeller both involve rotating blades, their roles differ: an impeller acts on a fluid within a machine, while a propeller generates thrust by acting on an external fluid such as air or water.
nounA rotating component with blades or vanes that drives a liquid or gas through a pump, turbine, or similar machine. Also refers more generally to any device that impels or sets a fluid in motion.
- A rotating blade or set of blades that drives a fluid through a pump or other machine.
- A component that accelerates a fluid by imparting motion or energy to it.
"The pump's impeller forces water through the narrow outlet at high pressure."
"A worn impeller can cause the pump to become noisy and lose pressure."
"The engine uses a turbine impeller to draw air into the compressor."
The plural is used when referring to multiple such rotating components.
"The system contains four impellers arranged in a single housing."
An impeller turns motion into pressure: its spinning blades are what make many pumps push water where it needs to go.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does impeller come from?
“Impeller” is formed from “impel,” meaning to drive or urge forward, with the agent suffix “-er.” The underlying Latin verb impellere means to drive or push forward, and is related to propel and other English words derived from the same root. In modern English, impeller developed as a technical term for a rotating mechanism that imparts motion or energy to a fluid.
How impeller is actually used
The term is chiefly technical and is used in engineering contexts. In pump terminology, it can refer either to the entire rotating assembly or specifically to its bladed disc, depending on the context.
Easily confused with impeller
An impeller moves or compresses a fluid within a machine, whereas a propeller is designed primarily to propel an aircraft or vessel through air or water.