1550s, "state of being crowded" (now obsolete); 1640s, "fact of occurring often;" from Latin frequentia "an assembling in great numbers, a crowding; crowd, multitude, throng," from frequentem (see frequent). Sense in physics, "rate of recurrence," especially of a vibration, is from 1831. In radio electronics, frequency modulation (1922, abbreviated F.M.) as a system of broadcasting is distinguished from amplitude modulation (or A.M.).
双语例句
1. Their instruments detected very faint radiowaves at a frequency of 3 kilohertz.
他们的仪器检测到一个3千赫的微弱无线电波。
来自柯林斯例句
2. Fatal road accidents have decreased in frequency over recent years.
近年来致命交通事故发生率已经下降。
来自《权威词典》
3. If we can know their frequency we will monitor their talking.
如果我们知道他们的频率,我们就能监听他们的谈话.
来自《简明英汉词典》
4. The drug can reduce the frequency and severity of attacks.
这种药能降低发病次数和严重程度.
来自《简明英汉词典》
5. Fatal accidents have decreased in frequency over recent years.
