sheaf

名词 n. 动词 v.
中文释义
发音 shēf

英文释义

名词 n.
  1. A quantity of the stalks and ears of wheat, rye, or other grain, bound together; a bundle of grain or straw.
    — O, let me teach you how to knit again This scattered corn into one mutual sheaf, These broken limbs again into one body.
  2. Any collection of things bound together.
    — a sheaf of paper
  3. A bundle of arrows sufficient to fill a quiver, or the allowance of each archer.
    — The sheaf of arrows shook, and rattled in the case.
  4. A quantity of arrows, usually twenty-four.
    — Arrows were anciently made of reeds, afterwards of cornel wood, and occasionally of every species of wood: but according to Roger Ascham, ash was best; arrows were reckoned by sheaves, a sheaf consisted of twenty-four arrows.
  5. A sheave.
  6. An abstract construct in topology that associates data to the open sets of a topological space (i.e. a presheaf) in such a way so as to make the local and global data compatible, generalizing the situation of functions, fiber bundles, manifold structure, etc. on a topological space. Formally, a presheaf ℱ whose sections are, in a technical sense, uniquely determined by their restrictions onto smaller sets: that is, given an open cover U_i of U:; If two sections over U agree under restriction to every U_i, then the sections are the same.
  7. An abstract construct in topology that associates data to the open sets of a topological space (i.e. a presheaf) in such a way so as to make the local and global data compatible, generalizing the situation of functions, fiber bundles, manifold structure, etc. on a topological space. Formally, a presheaf ℱ whose sections are, in a technical sense, uniquely determined by their restrictions onto smaller sets: that is, given an open cover U_i of U:; Given a family of sections s_i∈ℱ(U_i) such that all pairs (s_i,s_j) agree under restriction to U_i∩U_j, there is a (unique) section s over U whose restriction to U_i is s_i.
动词 v.
  1. To gather and bind into a sheaf; to make into sheaves transitive
    — to sheaf wheat
  2. To collect and bind cut grain, or the like; to make sheaves. intransitive
    — They that reap must sheaf and bind; Then to cart with Rosalind.

词形变化

sheaves plural sheafs plural sheafs present,singular,third-person sheafing participle,present sheafed participle,past sheafed past

词汇关系

衍生词
B-sheaf capsheaf cosheaf eigensheaf indsheaf sheafification sheafless sheaflike sheaf theory sheafwise sheafy structure sheaf subsheaf wheatsheaf

词源

词源 1
From Middle English scheef, from Old English sċēaf, from Proto-West Germanic *skaub, from Proto-Germanic *skauba- (“sheaf”).
Cognates
Akin to West Frisian skeaf (“sheaf”), Dutch schoof (“sheaf”), German Schaub, Old Norse skauf (“a fox's tail”). Compare further Gothic 𐍃𐌺𐌿𐍆𐍄 (skuft, “hair of the head”), German Schopf (“tuft”).
词源 2
From Middle English scheef, from Old English sċēaf, from Proto-West Germanic *skaub, from Proto-Germanic *skauba- (“sheaf”).
Cognates
Akin to West Frisian skeaf (“sheaf”), Dutch schoof (“sheaf”), German Schaub, Old Norse skauf (“a fox's tail”). Compare further Gothic 𐍃𐌺𐌿𐍆𐍄 (skuft, “hair of the head”), German Schopf (“tuft”).
0 次浏览 数据来源: Wiktionary