(a) [U] thick cloud of tiny drops of water close to or just above land or sea; thick mist 雾: Dense fog is covering roads in the north and visibility is very poor. 浓雾笼罩了北部的公路, 能见度很低. * Patches of fog will clear by mid-morning. 早晨一过局部地区的雾气就能消散. (b) [C] instance or period of this 雾; 有雾时: We get heavy fogs on this coast in winter. 这里的海边冬季有浓雾. =>Usage 见所附用法. 
[C, U] (area of) cloudiness on a photographic negative, etc, making the image unclear （摄影底片等上的）灰雾. 
(idm 习语) in a fog puzzled and confused 困惑; 迷惑: I'm in a complete fog about computer technology I don't understand it at all. 我对计算机技术如堕五里雾中--完全不懂.> fog v (-gg-)
1 [I, Ip, Tn, Tn.p] cover (sth) or become covered with fog 雾气笼罩（某物）; 有雾气: The windscreen has fogged (over/up). 挡风玻璃让雾气遮住了. * Steam has fogged the bathroom mirror. 水蒸气把浴室里的镜子遮住了.
2 (a) [Tn] cause cloudiness on (a photographic negative, etc) 使（摄影底片等上）产生灰雾: Shut the door or the light will fog the film. 把门关上, 不然亮光能使底片发灰. (b) [I] (of a photographic negative, etc) become cloudy （指摄影底片等）变灰.
3 [Tn] puzzle or confuse (sb) 使（某人）迷惑或困惑:I'm a bit fogged by these instructions. 这些说明把我搞得有些糊涂了.
4 [Tn] obscure or confuse (sth being discussed) 使（正在讨论的事物）变模糊或混淆不清: complicated language that just fogs the real issues 把实质问题弄得模糊不清的复杂的语言.
foggy adj (-ier, -iest) 1 not clear because of fog; very misty 有雾的; 雾气蒙蒙的: foggy weather 有雾的天气 * a foggy day 雾天. 2 obscure; confused; vague 模糊的; 混乱的; 朦胧的: His ideas on this subject are a bit foggy. 他对这个问题的看法有些模糊.
(idm 习语) not have the faintest/foggiest => faint1.# `fog-bank n mass of dense fog on the sea 平流雾（海面上的浓雾）; 雾堤.
`fog-bound adj unable to travel or operate normally because of fog; trapped by fog 因雾而不能正常行进或运行的; 被雾困住的: fog-bound planes, passengers 因雾停飞的飞机﹑ 因雾滞留的旅客 * a fog-bound airport, harbour 因雾而关闭的机场﹑ 港口.
`fog-horn n instrument that makes a loud blaring noise to warn ships of danger when it is foggy 雾角; 雾号; 雾笛: (joc or derog 谑或贬) He's got a voice like a fog-horn, ie a loud, harsh voice. 他的嗓音像雾角（大而刺耳）.
`fog-lamp n powerful light on the front of a car, etc for use in fog 雾灯（汽车等在雾天使用的前部强光灯）.
NOTE ON USAGE 用法: Fog, mist and haze are all clouds of water vapour at ground level and above. *fog﹑ mist﹑ haze均为地面及地面以上的水蒸气. They indicate different degrees of thickness 这几个词表示的浓度有所不同: fog is the thickest and haze the least thick. *fog最浓, haze最薄. Haze also occurs when it is very hot *haze在天气炎热时也会出现: a heat-haze 热天的薄雾. Smog is an unhealthy mixture of smoke and fog in the air of some industrial cities. *smog是在一些工业城市的空气中烟与雾的混合物, 是有害於健康的.