背はい景けい放ほう射しゃはいけいほうしゃMeanings1nounbackground radiationScientific term used in physics and astronomy, often referring to cosmic microwave background radiation or other diffuse radiation fields.宇う宙ちゅう背はい景けい放ほう射しゃはビッグバンの証しょう拠ことされて