| 释义 |
bract /brakt /noun Botany A modified leaf or scale, typically small, with a flower or flower cluster in its axil. Bracts are sometimes larger and more brightly coloured than the true flower, as in poinsettia.Even though a continuum was observed between the ‘true’ leaves and bracts, for simplicity all primordia bearing an axillary flower were considered as a bract....- In addition to a terminal flower there may be several smaller lateral flowers in the axil of cupular bracts, each surrounded by its own small cupule.
- Grasses and bamboos are known to have large deposits of silica in the tissues of leaf blades and inflorescence bracts.
Derivatives Origin Late 18th century: from Latin bractea 'thin plate of metal'. Rhymes abreact, abstract, act, attract, compact, contract, counteract, diffract, enact, exact, extract, fact, humpbacked, impact, interact, matter-of-fact, pact, protract, redact, refract, retroact, subcontract, subtract, tact, tract, transact, unbacked, underact, untracked |