(a) moving or done quickly; rapid 快的; 迅速的; 敏捷的: a fast car, horse, runner, ie one that can move at high speed 跑得很快的汽车﹑ 马﹑ 人. (b) happening quickly 迅速发生的; 短暂的: a fast journey, trip, etc 匆匆之行﹑ 一趟. 
(of a surface) producing or allowing quick movement （指物体表面）可供快速运动的: a fast road, pitch 快速车道﹑ 平滑的球场. 
(of a watch or clock) showing a time later than the true time （指钟表）走得过快的: I'm early my watch must be fast. 我来早了--准是我的表快了. * That clock's ten minutes fast. 那钟快了十分钟. 
(of photographic film) very sensitive to light, allowing a short exposure （指胶卷）感光快的, 曝光时间短的. 
(dated 旧) (of a person) spending too much time and energy on pleasure and excitement; reckless （指人）耽於享乐的, 放荡的: lead a fast life 过放荡的生活.
(idm 习语) fast and `furious (of games, parties, shows, etc) lively and energetic （指游戏﹑ 聚会﹑ 表演等）生动活泼的. pull a fast one => pull2.> fast adv
1 quickly 快地; 迅速地: Can't you run any faster than that? 你不能跑得再快点吗? * Night was fast approaching. 黑夜转瞬而至.
2 (idm 习语) run, etc as fast as one's legs can carry one as fast as one is able 尽快地（跑等）.
# fast `food food such as hamburgers, chips, etc that can be cooked easily, and is sold by restaurants to be eaten quickly or taken away 快餐食品: [attrib 作定语] a ,fast food `counter, `restaurant 快餐柜台﹑ 快餐店.
fast time (US infml 口) = summer time (summer).