1 B1 neutral
To block a pipe, drain, or passage with an accumulation of material so that nothing can flow through.
"Grease from cooking had clogged up the kitchen drain completely."
separable
clog up
B1 informal separable transitive/intransitive
To block something gradually with an accumulation of material, making it unable to flow or function properly.
In plain English
When something gets completely blocked and stops working because too much stuff has built up inside it.
What does "clog up" mean?
3 meanings, ordered from most common to least. Color-coded by CEFR level.
2 B1 idiomatic informal
To fill a road, system, or space to the point where it can no longer function effectively.
"The extra traffic from the festival completely clogged up the town centre."
separable
3 B2 idiomatic informal
To overwhelm or overload a system, inbox, or process so that it slows down or stops working.
"Spam emails were clogging up her inbox and making it impossible to find important messages."
separable
Literal vs figurative
Words literally mean
To block ('clog') completely ('up') so nothing can pass through.
Actually means
When something gets completely blocked and stops working because too much stuff has built up inside it.
Usage tip
Used both literally (pipes, drains, arteries) and figuratively (systems, processes, roads). The particle 'up' intensifies the sense of complete blockage. Very common in everyday British English.
Words that pair with "clog up"
Natural word combinations native speakers use most often.
drain pipe road artery system filter
How to conjugate "clog up"
The five tense forms you'll use most often.
Base
clog up
I/you/we/they
3rd person
clogs up
he/she/it
Past simple
cloged up
yesterday
Past participle
cloged up
have + pp
-ing form
cloging up
continuous
Hear "clog up" in the wild
Listen to native speakers using "clog up" in real YouTube videos — click a clip to watch it on Looplines.
Keep exploring
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