squeeze or pack tightly into a specified space

four of us were jammed in one compartment

people jammed their belongings into cars

mum, dad, and I jammed into the pickup truck

become or make unable to move or work due to a part seizing up or becoming stuck

the photocopier jammed

the doors were jammed open

improvise with other musicians, especially in jazz or blues

he had the opportunity to jam with Atlanta blues musicians

make (fruit) into jam