放ほう射しゃ性せい崩ほう壊かいMeaningsNoun1. radioactive decayKanji used放release射shoot性nature (of a person)崩crumble壊breakPitch accentほうしゃせいほうかいComposed of放ほう射しゃ性せいradioactiveNoun崩ほう壊かいcollapse; crumbling; breaking down; caving in; (radioactive) decay; disintegrationNoun