1
- the rate at which someone or something moves or operates or is able to move or operate速度：
the car has a top speed of 147 mph.
汽车最高时速是147英里。
1.1
- mass noun rapidity of movement or action快; 迅速：
the accident was due to excessive speed
这次事故是因为速度太快而造成的
figurative 〈喻〉they were bemused by the speed of events.
他们被事件的迅速变化惊呆了。
1.2
- each of the possible gear ratios of a bicycle（自行车的）挡, 变速挡。
1.3
- chiefly US or dated each of the possible gear ratios of a motor vehicle〈主美或旧〉机车的排挡。
1.4
- the sensitivity of photographic film to light感光度。
1.5
- the light-gathering power or f-number of a camera lens快门速度。
1.6
- the duration of a photographic exposure照片曝光的时间。
2
- mass noun informal an amphetamine drug, especially methamphetamine〈非正式〉苯异丙胺, 安非他明（尤指甲基苯丙胺）。
3
- mass noun archaic success; prosperity〈古〉成功; 繁荣：
wish me good speed.
祝我成功吧。
(past and past participle sped)
1
- no obj., with adverbial of direction move quickly快速移动：
I got into the car and home we sped.
我上了车, 迅速向我们家里驶去。
1.1
- (past and past participle speeded)no obj.(of a motorist) travel at a speed that is greater than the legal limit（驾车者）违章超速行驶：
the car that crashed was speeding.
撞毁的那辆车超速行驶了。
1.2
- (past and past participle speeded) (speed up) move or work more quickly加快速度：
you force yourself to speed up because you don't want to keep others waiting.
你要强迫自己加快速度, 因为你也不想让别人一直等你。
1.3
- (past and past participle speeded)with obj. cause to move, act, or happen more quickly使加速：
recent initiatives have sought to speed up decision-making.
最近的主动是为了寻求加快决策。
2
- with obj. archaic make prosperous or successful〈古〉使兴旺发达; 帮助成功：
may God speed you.
祝你成功。
3
- no obj. informal take or be under the influence of an amphetamine drug〈非正式〉用（脱氧麻黄碱之类的）兴奋剂成瘾; 受到（脱氧麻黄碱之类的）影响：
more kids than ever are speeding, tripping, and getting stoned.
越来越多的年轻人服用兴奋剂、吸毒和酗酒。
短语
at speed
- quickly迅速地：
a car flashed past them at speed.
一辆车从他们身边疾驰而过。
up to speed
1
- operating at full speed全速运行。
1.1
- (of a person or company) performing at an anticipated rate or level（人, 公司）以预期的速度（或水平）进行。
1.2
- (of a person) fully informed or up to date（人）无所不晓的; 掌握最新信息的, 跟上时代的：
that reminds me to bring you up to speed on the soap opera.
那提醒我要让你跟上那剧情。
派生词
speeder
noun词源
Old English spēd (noun), spēdan (verb), from the Germanic base of Old English spōwan 'prosper, succeed', a sense reflected in early usage.