Antonyms of adv downriver

1 sense of downriver

Sense 1
downriver, downstream -- (away from the source or with the current)
       Antonym of upriver (Sense 1)
      => upriver, upstream -- (toward the source or against the current)

Synonyms of adv downriver

1 sense of downriver

Sense 1
downriver, downstream -- (away from the source or with the current)