ENGLISH
REFERENCE

clag up

phr. v..
C1 Advanced Oxford

phr. v.. to become blocked or stuck with something thick and sticky so that a machine or system stops working well.

phr. v.. to become obstructed or congested by a sticky or viscous substance; often used in mechanical or metaphorical contexts to describe a loss of efficiency.


SIMPLE

The printer keeps clagging up because of the cheap ink.

CONTEXTUAL

If you don't clean the filter regularly, it will clag up with dust and grease.

COMPLEX

The gears began to clag up as the lubricant thickened in the freezing temperatures, eventually bringing the entire assembly to a halt.

Particles
up
Separability
optional
Pattern
clag + (object) + up
Usage

often used with the preposition 'with' to name the substance causing the blockage.

Teaching tip

this is a more informal and vivid alternative to 'clog up' or 'block'; it is particularly common in British English and technical hobbyist circles.

Pitfall

The pipe clagged.The pipe clagged up.the particle 'up' is necessary to complete the meaning of becoming fully blocked.

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