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jam something up
1. to clog up something; to impede or block the movement of or through something. Rachel jammed traffic up when her car stalled. All the leaves and branches jammed up the sewer.
2. Fig. to force something upwards in haste or anger. Who jammed the window up? Wally jammed up the window and nearly broke it.
jam something up something
to thrust something up something. She poked the broom handle up the chimney, hoping to force the bird to fly out. She jammed it up a few times, but it had no effect.
1. To become blocked, congested, or clogged: The traffic jammed up on the highway.
2. To cause something to become blocked, congested, or clogged: Some hair jammed the pipes up. You jammed up the drain with leftover food.