to press, squeeze, or wedge tightly between bodies or surfaces, so that motion or extrication is made difficult or impossible

The ship was jammed between two rocks.

to bruise or crush by squeezing

She jammed her hand in the door.

to fill too tightly; cram

He jammed the suitcase with clothing.

to press, push, or thrust violently, as into a confined space or against some object

She jammed her foot on the brake.

to fill or block up by crowding; pack or obstruct

Crowds jammed the doors.

to put or place in position with a violent gesture (often fol. by on )

He jammed his hat on and stalked out of the room.

to make (something) unworkable by causing parts to become stuck, blocked, caught, displaced, etc.

to jam a lock.

Radio .

to interfere with (radio signals or the like) by sending out other signals of approximately the same frequency.

(of radio signals or the like) to interfere with (other signals).

to play (a piece) in a freely improvised, swinging way; jazz up

to jam both standard tunes and the classics.

Nautical . to head (a sailing ship) as nearly as possible into the wind without putting it in stays or putting it wholly aback.

to become stuck, wedged, fixed, blocked, etc.

This door jams easily.

to press or push, often violently, as into a confined space or against one another

They jammed into the elevator.

(of a machine, part, etc.) to become unworkable, as through the wedging or displacement of a part.

Jazz . to participate in a jam session.

the act of jamming or the state of being jammed.

a mass of objects, vehicles, etc., jammed together or otherwise unable to move except slowly

a log jam; a traffic jam.

Informal . a difficult or embarrassing situation; fix

He got himself into a jam with his boss.

jam session.

noun

benefit , boon

noun

bind , box , corner , difficulty , dilemma , fix , hole , hot water , pickle * , plight , predicament , problem , quandary , scrape , spot , strait , troublenotes:jam is a thick mixture made from fruit pulp and sugar; jelly is made from fruit juice boiled with sugar; preserves are fruit preserved whole or in large pieces and cooked with sugar; marmalade is boiled fruit pulp , rinds , and sugar , gridlock , immobilization , stoppage , deep water , dutch , hot spot , quagmire , soup , trouble

verb

bear , bind , block , cease , clog , congest , cram , crowd , crush , elbow , force , halt , jam-pack , jostle , obstruct , pack , press , push , ram , squash , squish , stall , stick , stuff , tamp , throng , wad , wedgenotes:jam is a thick mixture made from fruit pulp and sugar; jelly is made from fruit juice boiled with sugar; preserves are fruit preserved whole or in large pieces and cooked with sugar; marmalade is boiled fruit pulp , rinds , and sugar , load , mob , bruise , compress , congestion , corner , dilemma , hole , pickle , pinch , predicament , quandary , scrape , squeeze , stop , tie up , trouble , wedge in