upstream

Everyday

1. Upstream means towards the source of a river or stream, against the way the water flows. tree →
2. An upstream place is further up the river, nearer its source. tree →
3. (informal) Swimming upstream can mean doing something hard, against what most people do or want. tree →

In the lessons

In geography lessons on rivers: the source is upstream and the mouth is downstream; salmon swim upstream to lay eggs. In science, pollution upstream can flow down and affect places downstream. In maths, problems with boats going upstream mean the boat's speed minus the river's speed. Phrases: «swim upstream», «travel upstream», «upstream of the bridge».

Examples

• Salmon swim upstream to lay their eggs. tree →
• We paddled the canoe upstream, which was hard work. tree →
• The village upstream has cleaner water. tree →
• Pollution upstream can harm fish downstream. tree →
• A boat goes 10 km/h in still water and the river flows at 2 km/h, so upstream it goes 8 km/h. tree →
• The source of the river is upstream from here. tree →
• Remember, you are upstream and I am downstream." tree →

Note

Adverb and adjective. Opposite: downstream. Maths rule: upstream speed = boat speed − current speed; downstream speed = boat speed + current speed.