discoid

/ˈdi-ˌskȯid/ (ame, mw)

discoid — adjective

  • discoidpositive
  • more discoidcomparative
  • most discoidsuperlative

1. having the shape of a thin, flat circle, like a coin or a small plate.

1.形容詞C2
釋義

having the shape of a thin, flat circle, like a coin or a small plate.

例句

Ryan held up a discoid pebble he had found by the river.

attributive: discoid + noun

The ancient coin had a discoid form with worn markings on both sides.

同義詞
  • disk-shaped

    the everyday equivalent; preferred in non-technical writing

  • discoidal

    a less common variant adjective, mostly in scientific texts

  • circular

    covers any flat circle but does not imply the thin, plate-like body of 'discoid'

反義詞
  • spherical

    fully three-dimensional ball shape, opposite of flat

文法句型

discoid + noun

be + discoid

用法筆記

Frequently attributive, modifying a concrete noun whose shape is being described. Largely a written or technical word — everyday English prefers 'disk-shaped' or 'round and flat'.

常見錯誤

❌The pizza was discoid and tasty.
✅The pizza was round and flat, and tasty.
💡'discoid' sounds technical; everyday food contexts prefer plain words.

2. in botany, describing a flower head that is made up only of small tubular floret

2.形容詞C2
釋義

in botany, describing a flower head that is made up only of small tubular florets in the central disk, with no outer ray petals.

例句

Tansy plants in Hassan's garden produce small, yellow, discoid flower heads.

attributive: discoid + flower head

Some thistles have discoid heads, missing the bright petals seen on daisies.

同義詞
  • rayless

    describes the same flower head from the angle of missing ray petals

反義詞
  • radiate

    having both central disk florets and outer ray petals, like a daisy

  • ligulate

    made up of strap-shaped ray florets only, with no central disk

文法句型

discoid + flower / floret / head

用法筆記

Specialist botanical term; appears almost only in textbooks, plant keys, and field guides. Contrast with 'radiate' or 'ligulate' heads that carry visible outer petals.

常見錯誤

❌a discoid rose with red petals.
✅a discoid head of small tube flowers, with no outer petals.
💡by definition, this sense rules out showy outer petals.

3. in medicine, describing a skin condition that shows small, round, flat patches o

3.形容詞C2
釋義

in medicine, describing a skin condition that shows small, round, flat patches on the skin.

例句

Mira was diagnosed with discoid lupus after the round patches stayed for months.

collocation: discoid lupus

The dermatologist showed Ritu photographs of typical discoid lesions on the cheeks.

collocation: discoid lesions

同義詞
  • nummular

    literally 'coin-shaped'; used of eczema with the same round-patch pattern

文法句型

discoid + lesion / rash / lupus

用法筆記

Almost always attributive in fixed medical compounds such as 'discoid lupus', 'discoid eczema', 'discoid lesion'. Outside clinical writing, learners are unlikely to meet this sense.

常見錯誤

❌My arm was discoid yesterday.
✅I had a small discoid patch on my arm yesterday.
💡'discoid' describes the patch or lesion, not the body part itself.