Definition of groundsel in US English:

groundsel

noun

  • 1A widely distributed plant of the daisy family, with yellow rayless flowers.

    Genus Senecio, family Compositae: several species, in particular the common groundsel (S. vulgaris), which is a common weed. See also giant groundsel

    • ‘While studying a drab little plant called the groundsel, he was struck by the fact that plants of the same genetic variety could look very different in different environments.’
    • ‘Add glyphosate for effective control of common chickweed, wild carrot, poison hemlock, cressleaf groundsel, and dense populations of dandelion.’
    • ‘The image, of a groundsel, shows Britain's newest species of plant - found next to the railway station car park in York.’
    • ‘In the last analysis, groundsels breeding groundsels is not evolution - that's groundless!’
    • ‘Growing among the tufa formations in the marshes are dock, giant red Indian paintbrush, groundsel, horsetail, Rocky Mountain iris, an aquatic speedwell, stinging nettle (which often surrounds each tower), and willow herb.’
  • 2

    variant spelling of groundsill

Origin

Old English gundæswelgiæ (later grundeswylige), probably from gund ‘pus’ + swelgan ‘to swallow’ (with reference to its use in poultices). The later form may be by association with ground, and refer to the plant's rapid growth.

Pronunciation

groundsel

/ˈɡraʊn(d)səl//ˈɡroun(d)səl/