Definition of quack grass in English:

quack grass

Pronunciation /ˈkwak ˌɡras/ /ˈkwæk ˌɡræs/

noun

North American
another term for couch
‘A recent example is a cross with bread wheat and quack grass.’
  • ‘My worst weeds are the perennials that spread with runners, like quack grass.’
  • ‘In his pasture, edible weeds like dandelion, chicory, quack grass and even stinging nettles are allowed to thrive.’
  • ‘Fast-growing fall cover crops outcompete late-season weeds like quack grass and chickweed.’
  • ‘However, many people have different kinds of thick bladed grass in their lawn such as quack grass.’

Origin

Early 19th century quack, variant of quick, northern form of quitch.