/ dʒæm; NAmE / noun , verb
■ noun
SWEET FOOD
1.
[ U , C ] a thick sweet substance made by boiling fruit with sugar, often sold in jars and spread on bread :
strawberry jam
recipes for jams and preserves
( BrE )
a jam doughnut
—compare jelly , marmalade
MANY PEOPLE / VEHICLES
2.
[ C ] a situation in which it is difficult or impossible to move because there are so many people or vehicles in one particular place :
The bus was delayed in a five-mile jam.
As fans rushed to leave, jams formed at all the exits.
—see also traffic jam
MACHINE
3.
[ C ] a situation in which a machine does not work because sth is stuck in one position :
There's a paper jam in the photocopier.
•
IDIOMS
- be in a jam
- jam tomorrow
—more at money
■ verb
( -mm- )
PUSH WITH FORCE
1.
[ vn + adv. / prep. ] to push sth somewhere with a lot of force :
He jammed his fingers in his ears.
A stool had been jammed against the door.
STOP MOVING / WORKING
2.
jam (sth) (up) to become unable to move or work; to make sth do this :
[ v ]
The photocopier keeps jamming up.
[ vn ]
There's a loose part that keeps jamming the mechanism.
[ v - adj ]
The valve has jammed shut.
[ vn - adj ]
He jammed the door open with a piece of wood.
PUT INTO SMALL SPACE
3.
[+ adv. / prep. ] to put sb/sth into a small space where there is very little room to move
SYN squash , squeeze :
[ vn ]
Six of us were jammed into one small car.
We were jammed together like sardines in a can.
The cupboards were jammed full of old newspapers.
[ v ]
Nearly 1 000 students jammed into the hall.
—see also jam-packed
FILL WITH PEOPLE / THINGS
4.
[ vn ] jam sth (up) (with sb/sth) to fill sth with a large number of people or things so that it is unable to function as it should
SYN block :
Viewers jammed the switchboard with complaints.
RADIO BROADCAST
5.
[ vn ] ( technical ) to send out radio signals to prevent another radio broadcast from being heard
PLAY MUSIC
6.
[ v , vn ] to play music with other musicians in an informal way without preparing or practising first
•
IDIOMS
- jam on the brake(s) | jam the brake(s) on
••
WORD ORIGIN
verb and noun senses 2 to 3 early 18th cent.: probably symbolic; compare with cram .
noun sense 1 mid 18th cent.: perhaps from jam (verb).