Denshi Jisho — Online Japanese dictionary

固執 こしつ adherence (e.g. to ideas, beliefs, a pet theory) (negative nuance); persistence; insistence; stubbornness
Common word, Noun, Suru verb 
固執 こしゅう adherence (e.g. to ideas, beliefs, a pet theory) (negative nuance); persistence; insistence; stubbornness
Noun, Suru verb 

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