thread（n.）
源自古英语 þræd “细绳，尤指被拧成的”（与 þrawan “拧”有关），来自原始日耳曼语 *thredu- “拧成的纱线” （源自古撒克逊语 thrad、古弗里西亚语 thred、中古荷兰语 draet、荷兰语 draad、古高地德语 drat、德语 Draht、古诺尔斯语 þraðr），字面意思是“被拧的”，来自PIE根词 *tere- (1) “摩擦、转动”的衍生形式。意指“螺钉的螺旋脊线”的用法始于1670年代。Threads，指“衣服”的俚语，始于1926年的美国英语。
The silk line, as spun by the worm, is about the 5000th part of an inch thick; but a spider's line is perhaps six times finer, or only the 30,000th part of an inch in diameter, insomuch, that a single pound of this attenuated substance might be sufficient to encompass our globe. [John Leslie, "Elements of Natural Philosophy," Edinburgh, 1823]
蚕丝的厚度约为五千分之一英寸；但蜘蛛丝可能更细约六倍，即仅为三万分之一英寸的直径，以至于一磅这种纤细物质足以环绕地球。 [约翰·莱斯利, "自然哲学要素," 爱丁堡, 1823年]
Nuts and bolts you know as little things that put big things together. Actually, our whole industrial civilization hangs by a thread—a screw thread. [Popular Science, March 1949]
你知道螺丝和螺栓是用来把大件物品组合在一起的小部件。实际上，我们整个工业文明就靠一根线——一根螺纹（来悬挂）。[《科学人》杂志, 1949年3月]