1 B2 neutral
To block or stop the movement of a machine, object, or passage.
"A folded label jammed up the printer again."
separable
jam up
B2 neutral separable transitive/intransitive
To block, crowd, or cause something to get stuck and stop moving smoothly.
In plain English
make something stuck or too crowded
What does "jam up" mean?
3 meanings, ordered from most common to least. Color-coded by CEFR level.
2 B2 idiomatic neutral
To make traffic, movement, or progress slow because of crowding or blockage.
"The accident jammed up the highway for miles."
separable
3 C1 idiomatic informal
To put someone in trouble or a difficult position.
"One missing signature jammed us up with the bank."
separable
Literal vs figurative
Words literally mean
To force something into a jam or stuck state.
Actually means
make something stuck or too crowded
Usage tip
Used for machinery, traffic, and schedules. In some regional uses, 'jammed up' can also mean in trouble or in a difficult situation.
Words that pair with "jam up"
Natural word combinations native speakers use most often.
traffic printer machine road schedule lines
How to conjugate "jam up"
The five tense forms you'll use most often.
Base
jam up
I/you/we/they
3rd person
jams up
he/she/it
Past simple
jamed up
yesterday
Past participle
jamed up
have + pp
-ing form
jaming up
continuous
Hear "jam up" in the wild
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Other ways to say "jam up"
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