Denshi Jisho — Online Japanese dictionary

崩壊 ほうかい 1: collapse; crumbling; breaking down; caving in;
2: decay (Physics term)
Common word, Noun, Suru verb 
崩壊系列 ほうかいけいれつ decay chain
Noun 
崩壊寸前 ほうかいすんぜん on the brink of collapse; in a state of near-collapse
Noun 

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