The phrase "wave length" refers to the length of a wave from one peak or crest to the next. It is used to describe the distance between repeating patterns in waves, such as light, sound, or other types of waves.
We're on the same wave length today with beauty items! (ablondesmoment.com)
With wave lengths of up to 300 meters some days this is definitely a must for any surfing enthusiast. (surfvoucher.com)
He says he loves me and wants to grow old with me... I think we're on different wave lengths regarding what taking time means. (thecoupleconnection.net)