Denshi Jisho — Online Japanese dictionary

反発 はんぱつ 1: to repel; to oppose; to revolt; to react sharply (against);
2: (Noun) opposition; rebellion; resistance; backlash;
3: rally; recovery (e.g. in stock prices); rebound;
4: (Suru verb) to rally; to recover; to rebound
Common word, Suru verb 
反発 はんぱつりょく repellent force; resiliency; elasticity
Noun 

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