Crowded (7)
'crowded' is the definition.
(jamming is a kind of crowding)
This is all the clue.
(Other definitions for jammed that I've seen before include "Stuck and immobilized" , "crushed" , "packed" , "Like a doughnut" , "in a confined space" .)
'crowded' is the definition.
(swarming is a kind of crowding)
This is the entire clue.
(Other definitions for swarmed that I've seen before include "crowded" , "(Of bees) flew en masse" , "Teemed (like bees)" .)