Upstream

['ʌpstriːm] or [,ʌp'strim]

(adj.) in the direction against a stream's current .

Edited by Eileen--From WordNet

(adv.) Toward the higher part of a stream; against the current.

Checked by Alden

adv. towards the upper part of a stream.—v.i. Upstream′ to stream up.

Checker: Williams