◙ noun 1. a shape produced by a curve that bends round and crosses itself • 环，圈 a length of thread, rope, or similar material, doubled or crossing itself, typically used as a fastening or handle • （线、绳或类似材料的）环，扣，圈 a curved stroke forming part of a letter (e.g. b, p) • 字母的环形部分（如b, p) (也作 loop line)a length of railway track which is connected at either end to the main line and on to which trains can be diverted to allow others to pass • （可改道的）会车线 (也作 loop road)a stretch of road that diverges from a main road and joins it again • 环行路 (也作 loop-the-loop)a manoeuvre in which an aircraft describes a vertical circle in the air • 翻筋斗 [Skating] a manoeuvre describing a curve that crosses itself, made on a single edge • [滑冰] 单刃转圈 [dated] a contraceptive coil • [旧] 节育环 short forinduction loop • induction loop. 的简称 2. a structure, series, or process the end of which is connected to the beginning • 环状结构（或系列）；循环过程 an endless strip of tape or film allowing continuous repetition • 无限循环 a complete circuit for an electric current • 回路 [Computing] a programmed sequence of instructions that is repeated until or while a particular condition is satisfied • [计算机] 循环 ◙ verb 1. [with obj. and adverbial] form (something) into a loop or loops;encircle • 环绕 »she looped her arms around his neck. 她把胳膊绕在他的脖子上。 [no obj., with adverbial] follow a course that forms a loop or loops • 绕行 »the canal loops for two miles through the city. 运河在城里绕了两英里。 put into or execute a loop of tape, film, or computing instructions • 放磁带；放电影；运行计算机指令 (也作 loop the loop)circle an aircraft vertically in the air • 绕着飞机翻筋斗
【IDIOMS】
◘ in (或 out of) the loop 1. (informal, chieflyUS)aware (or unaware) of information known to only a privileged few • [非正式，主美] （不）了解内幕 ◘ throw (或 knock) someone for a loop 1. [N. Amer. informal] surprise or astonish someone; catch someone off guard • [北美，非正式] 使惊奇，突袭
【语源】
1. late Middle English: of unknown origin; compare with Scottish Gaelic lùb 'loop, bend'