Definition of rill in English:



  • 1A small stream.

    • ‘Michael suggested the water should be channelled under the house to supply Robin's pond and a short rill in the back before being pumped to the front, where it supplies a fountain.’
    • ‘The river is about 30 m wide here, alternating between pools and rocky-bottomed shallow rills.’
    • ‘The rill was a parched ravine now, as though some convulsion of the earth had bled the region dry of its lifeblood.’
    • ‘Slowing as Sara's viewpoint neared the surface, more and more details became clearer - craters large and small, passing rills and distant mountains, boulders everywhere.’
    • ‘After a spell of rain, small rills are filled up with garbage.’
    • ‘A linked watercourse is planned, with cascades, ponds and rills.’
    brook, rivulet, runnel, streamlet, freshet
    View synonyms
    1. 1.1 A shallow channel cut in the surface of soil or rocks by running water.
      • ‘These rills generally develop in the same places each year.’
      • ‘But it is not quite a cascade, either, since the narrowness of the granite channel gives it something of the character of a formal rill.’
      • ‘Flow velocity increases, and the increased energy detaches more soil particles and transports them in tiny channels called rills.’
      • ‘These streams appear from the crevices of the rocks running through rills and gullies.’
      • ‘The characteristic forms of water erosion are rills and gullies.’
      • ‘As rills cut deeper and coalesce, gully erosion develops.’
      • ‘No evidence was observed of increased gully formation except in localized spots, nor was there any visible evidence of excessive rill or sheet erosion.’
    2. 1.2
      variant spelling of rille


Mid 16th century: probably of Low German origin.