Definition of discoid in US English:



  • Shaped like a disc.

    • ‘Heads on discoid plants have an extra whorl of disc florets instead of ray florets.’
    • ‘The distribution of psoriasis on extensor surfaces, scalp and natal cleft helps distinguish psoriasis from discoid eczema.’
    • ‘A further possibility is discoid lupus erythematosus, the technical term for an autoimmune dermatitis of dogs that is usually confined to the face and is frequently made worse by exposure to ultraviolet light.’
    • ‘It has been reported that 20 percent of patients with systemic lupus erythematosus will develop discoid skin lesions; however, most patients who have only cutaneous lupus at presentation will not progress to systemic disease.’
    • ‘Platelet activation is observed as a morphological change from the resting discoid state to activated spherical cells with pseudopods.’
    circular, disc-shaped, disc-like
    View synonyms


  • A thing that is shaped like a disc, particularly a type of ancient stone tool.

    • ‘The stone tool assemblage includes convex end scrapers, bifacially-flaked small knives, and flattened discoids and microliths.’
    • ‘Eighty-nine were flaked-stone tools; the ninetieth was a carefully shaped discoid, perhaps a mano or grinding stone.’
    • ‘Most identification centres around inclusions – zircon, glassy discoids which sometimes contain fern-like feathers and rutile crystals with blue halos.’
    • ‘Formal tools are rare but include scrapers, a discoid and two choppers.’
    • ‘Stone Age tools such as handaxes, cleavers, discoids and scrapers have been discovered in the region.’


Late 18th century: from Greek diskoeidēs, from diskos (see discus).