runoff

[ruhn-awf, -of] /ˈrʌnˌɔf, -ˌɒf/
noun
1.
something that drains or flows off, as rain that flows off from the land in streams.
2.
a final contest held to determine a victor after earlier contests have eliminated the weaker contestants.
3.
a deciding final contest held after one in which there has been no decisive victor, as between two contestants who have tied for first place.
4.
Also called rundown. a continual or prolonged reduction, especially in quantity or supply:
a runoff in bank deposits; a sharp runoff in business inventories.
5.
Stock Exchange. the final prices appearing on the ticker after the closing bell is rung for the trading day.
Origin
1850-55, Americanism; noun use of verb phrase run off; (def 2, 3) see -off
Examples from the web for runoff
  • The researchers expect less excess nutrients in the runoff as the plants on the roof continue to grow.
  • And our measurements confirm that that stream is contaminated with chemicals from runoff from the mine.
  • Typically, coal companies construct filtration ponds to capture sediments and valley-fill runoff.
  • The only sound was the slow drip of runoff from gutters and rooftops.
  • Encouraging the flow of information and catching the runoff.
  • They had set up rain barrels, a bat house, and landscaping to prevent runoff.
  • Storm runoff is not treated and flows directly into streams, lakes and other bodies of water nearby.
  • It is possible to cut back on nitrogen runoff but that of course requires regulation and creates expense, etc.
  • You'd reduce water use and end runoff by recycling water in a closed irrigation system.
  • Loam soils absorb water at an even pace without heavy puddling or runoff.
British Dictionary definitions for runoff

run off

verb (adverb)
1.
(intransitive) to depart in haste
2.
(transitive) to produce quickly, as copies on a duplicating machine
3.
to drain (liquid) or (of liquid) to be drained
4.
(transitive) to decide (a race) by a runoff
5.
(transitive) to get rid of (weight, etc) by running
6.
(intransitive) (of a flow of liquid) to begin to dry up; cease to run
7.
run off with
  1. to steal; purloin
  2. to elope with
noun
8.
  1. an extra race to decide the winner after a tie
  2. a contest or election held after a previous one has failed to produce a clear victory for any one person
9.
that portion of rainfall that runs into streams as surface water rather than being absorbed into ground water or evaporating
10.
the overflow of a liquid from a container
11.
(NZ) grazing land for store cattle
Word Origin and History for runoff
n.

also run-off, "precipitation water drained by streams and rivers," 1887, from run (v.) + off (adv.). Meaning "deciding race after a tie" is from 1873; electoral sense is attested by 1910, American English.

Encyclopedia Article for runoff

in hydrology, quantity of water discharged in surface streams. Runoff includes not only the waters that travel over the land surface and through channels to reach a stream but also interflow, the water that infiltrates the soil surface and travels by means of gravity toward a stream channel (always above the main groundwater level) and eventually empties into the channel. Runoff also includes groundwater that is discharged into a stream; streamflow that is composed entirely of groundwater is termed base flow, or fair-weather runoff, and it occurs where a stream channel intersects the water table.

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