Definition of downcut in English:

downcut

verb

[NO OBJECT]Geology
  • (of a river) erode downwards through its bed:

    ‘the New River began downcutting’
    ‘the effect of the downcutting’
    • ‘After two winters, Canon Creek has downcut approximately 3 feet and has a deeper, more defined channel.’
    • ‘Once a channel starts to downcut, it usually does not stop until it has caused a lot more erosion.’

Pronunciation:

downcut

/ˈdaʊnkʌt/