Definition of influent in English:



  • Flowing in.

    ‘some particles delivered in the influent streams settle in the reservoirs’
    • ‘The reactor system includes a treatment basin having an inlet for continuously receiving an influent stream and an outlet for continuously discharging an effluent stream, and contains a mixed liquor.’
    • ‘In case of the river Ganges, it is effluent in south-west while influent in the north of Calcutta.’
    • ‘Municipal water treatment plants must charge customers for the increased chemicals and electricity necessary for water treatment when influent raw water has high turbidity levels.’
    • ‘He was a fantastic racehorse and like a lot of Danehill's sons can become an influent sire.’
    • ‘The influent pump shaft acts as a lift station delivering raw sewage from a newly constructed 9.5-mile-long 18-foot diameter rock tunnel.’
    • ‘Use at least a 4-inch diameter sewer line (also known as influent line or distribution pipe) from the house to the lagoon.’
    • ‘Therefore, adjustments to the dosing system must be made when influent flows change substantially.’
    • ‘The influent solution was sparged continuously with N2 gas to maintain anoxic conditions for the bacteria and to prevent aerobic oxidation of the materials in the wastewater.’
    • ‘In summer, influent waters are commonly warm and enter the uppermost waters, but cooler rainwater falling at night may sink to the level of the thermocline before moving out into the basin.’
    • ‘The high sludge yields were caused by unexpectedly high and erratic levels of influent solids for which the builders were not responsible.’
    • ‘The influent waters carry not only solute loads, but also sediments both in suspension and along the bed of the streams.’


  • A stream, especially a tributary, which flows into another stream or lake.

    • ‘This proves that the presence of ASP effluent in the Knostrop influent is not detrimental to settlement and that the Knostrop influent is capable of good settlement with proper operation.’
    • ‘The method involves the steps of continuously flowing an influent into a treatment basin and continuously flowing an effluent out of the treatment basin into a clarifier.’
    • ‘Each system is designed to handle a certain volume of water per day, but the system is also tailored for the qualities of the specific influent.’
    • ‘Good examples of influent streams include the Nile, and the Colorado River in the southwestern United States.’
    • ‘In an extensive survey of U.S. wastewater treatment plants, Schulz has found perfluorinated compounds in influents and effluents.’
    brook, rivulet, rill, runnel, streamlet, freshet
    View synonyms


Late Middle English (as an adjective): from Latin influent- flowing in, from influere (see influence). The noun is recorded from the mid 19th century.