Synonyms/Hypernyms (Ordered by Estimated Frequency) of verb jam-pack

1 sense of jampack

Sense 1
jam, jampack, ram, chock up, cram, wad -- (crowd or pack to capacity; "the theater was jampacked")
       => stuff -- (cram into a cavity; "The child stuffed candy into his pockets")

Antonyms of adj jam-packed

1 sense of jam-packed

Sense 1
jammed, jam-packed, packed -- (filled to capacity; "a suitcase jammed with dirty clothes"; "stands jam-packed with fans"; "a packed theater")

INDIRECT (VIA crowded) -> uncrowded -- (having or allowing sufficient room; "an uncrowded train"; "an uncrowded view")

Similarity of adj jam-packed

1 sense of jam-packed

Sense 1
jammed, jam-packed, packed -- (filled to capacity; "a suitcase jammed with dirty clothes"; "stands jam-packed with fans"; "a packed theater")
       => crowded (vs. uncrowded) -- (overfilled or compacted or concentrated; "a crowded theater"; "a crowded program"; "crowded trains"; "a young mother's crowded days")