transverse wave
noun [ C ] physics specialized uk/ˈtrænzˈvɜːs ˌweɪv/ us/ˈtrænsˈvɜːrs ˌweɪv/
横波，横向波
a wave moving through a substance in which the particles are vibrating (= moving quickly backwards and forwards) at a 90 degree angle to the direction of the wave
Compare: longitudinal wave