Definition

1. Noun:
   • The process or action of forcing or pushing something out through a small opening by applying pressure: This refers to the act of expelling material, often in a continuous stream or shape, through a die or orifice.
   • An object or part that protrudes or sticks out from a surface: This refers to something that extends outward, forming a bulge, prominence, or projection.

Usage and Examples

• Noun (Process):

  • The extrusion of aluminum into beams is a common manufacturing process.
  • An unexpected extrusion of toothpaste from the bottom of the tube can be messy.

• Noun (Protruding Object):

  • The extrusion on the cliff face provided a perfect handhold for the climbers.
  • The bony extrusion on the dinosaur's skull was likely used for display.

Advanced Usage

• Technical/Manufacturing Context: In engineering and manufacturing, "extrusion" specifically describes a process where material is forced through a shaped die to create long objects of a fixed cross-sectional profile.
  • Plastic extrusion is used to make pipes, sheets, and filaments.
• Geological Context: In geology, it can refer to igneous rock that has been forced out in a molten state onto the Earth's surface.
  • The lava dome is an extrusion of viscous magma.

Variants and Related Words

• Extrude (verb): To force or push something out.
  • The machine extrudes hot plastic to form a tube.
• Extrusive (adjective): Relating to or formed by extrusion, especially of igneous rock.
  • Basalt is a common extrusive rock.

Synonyms

• Expulsion: The action of forcing something out.
• Protrusion: Something that sticks out from a surface.
• Projection: A part that extends outward beyond the main body or line.

Related Phrases and Compounds

• Extrusion molding: A manufacturing process for shaping plastic or metal.
• Hot extrusion: A process performed at an elevated temperature to reduce the force required.

Related Idioms

There are no common idioms that use the word "extrusion" as a core component.

Noun

1. squeezing out by applying pressure
   • an unexpected extrusion of toothpaste from the bottom of the tube
   • the expulsion of pus from the pimple
2. something that bulges out or is protuberant or projects from its surroundings
   • the gun in his pocket made an obvious bulge
   • the hump of a camel
   • he stood on the rocky prominence
   • the occipital protuberance was well developed
   • the bony excrescence between its horns