bước sóng

== Vietnamese == === Etymology === bước (“step”) +‎ sóng (“wave”). === Pronunciation === (Hà Nội) IPA(key): [ʔɓɨək̚˧˦ sawŋ͡m˧˦] (Huế) IPA(key): [ʔɓɨək̚˦˧˥ ʂawŋ͡m˦˧˥] ~ [ʔɓɨək̚˦˧˥ sɔŋ˦˧˥] (Saigon) IPA(key): [ʔɓɨək̚˦˥ ʂawŋ͡m˦˥] ~ [ʔɓɨək̚˦˥ sawŋ͡m˦˥] === Noun === bước sóng (physics) a wavelength