Plain English Meaning

A pinched, narrow passage inside the carburetor that speeds up the air flowing through it. Faster air means lower pressure and cooler temperature at that spot, and that combination is what pulls fuel into the air so the engine has a fuel-air mixture to burn.

Full Definition

The narrowed section inside a carburetor where intake air is forced to speed up as it passes through. This acceleration causes a drop in pressure and temperature, which draws fuel into the airstream and mixes it with the incoming air before it reaches the engine cylinders.

Context Anchor

Seen in carburetor icing and induction icing discussions, especially when explaining why ice can form inside the engine air intake system.

Derivation

Named after Giovanni , an 18th-century Italian physicist who studied how behave when forced through a narrowed passage. He showed that speeds up and pressure drops in the narrow section -- the principle the carburetor relies on to draw in fuel.