Denshi Jisho — Online Japanese dictionary

怖 こわ frightening; terrifying
Interjection, Usually written using kana alone 
畏怖 いふ awe; fear; fright
Noun, Suru verb 
恐怖 くふ fear; dread; dismay; terror; horror; scare; panic
Out-dated or obsolete kana, Noun, Suru verb 
恐怖 きょうふ fear; dread; dismay; terror; horror; scare; panic
Common word, Noun, Suru verb 
怖怖 こわごわ fearfully; timidly; cautiously; nervously
Adverb, Adverb taking the 'to' particle 
閉所恐怖 へいしょきょうふ claustrophobia; fear of confined spaces
Noun 

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