the distance between two similar points on a wave of energy, such as light or sound 波长 
Oxford Collocations Dictionaryadjective- long
- medium
- short
- …
- be tuned to
- on a/the wavelength
- on the same wavelength
the size of a radio wave that is used by a particular radio station, etc. for sending signals or broadcasting programmes （广播电台等使用的）频道，波道 Radio One has broadcast on this wavelength for years. 广播1 台已经用这个波长广播多年了。
Oxford Collocations Dictionaryadjective- long
- medium
- short
- …
- be tuned to
- on a/the wavelength
- on the same wavelength
Idioms
be on the same wavelength | be on somebody’s wavelength
- (informal)
to have the same way of thinking or the same ideas or feelings as somebody else 具有（与他人）相同的思路；合拍；与…所见略同 We work together but we aren’t really on the same wavelength. 我们一起工作，但我们并不真正志同道合。 My boss and I are just not on the same wavelength. 我和老板就是想不到一块儿去。