Denshi Jisho — Online Japanese dictionary

こく 1: severe; harsh; stringent; rigorous; strict; unfair;
2: (Usually written using kana alone) body (esp. of food, wine, etc.); weight; substance
Common word, Na-adjective, Noun 
かこく rigour; rigor; severity; cruelty; harsh
Common word, Na-adjective, Noun 
使 こくし exploitation; overuse; abuse
Common word, Noun, Suru verb 
こくじ resemblance; resemble
Common word, Noun, Suru verb, No-adjective 
ひどい cruel; awful; severe; very bad; serious; terrible; heavy; violent
Common word, Adjective, Usually written using kana alone 
かこく rigour; rigor; severity; cruelty; harsh
Na-adjective, Noun 
こくり an unsparing official
Noun 
むごい cruel; atrocious; merciless; inhuman; brutal
Adjective 
こくしょ intense heat
Common word, Noun 
ざんこく cruelty; harshness
Common word, Na-adjective, Noun 
れいこく cruelty; coldheartedness; relentless; ruthless
Common word, Na-adjective, Noun 
げんこく severity; rigor; rigour
Na-adjective, Noun 
こくぐう maltreatment
Noun, Suru verb 
こくぜい heavy taxation
Noun 
こくねつ intense heat
Noun 
こくはく cruel; inhumane
Na-adjective, Noun 
こくれつ severity
Na-adjective, Noun 
こっかん severe (intense) cold; depth of winter
Noun 
こっけい severe punishment
Noun 
ざんこく atrocity; cruelty; brutality
Na-adjective, Noun 
しい きびしい 1: severe; strict; rigid; unsparing; relentless;
2: stern; austere; grave; solemn; majestic;
3: intense (cold)
Adjective 
てひどい severe; harsh
Adjective 
こくひょう severe criticism; damnation
Common word, Noun, Suru verb, No-adjective 
しゅんこく severe (personality); unaffected by love
Noun 
事故 かこくじこ severe accident (esp. relating to a nuclear reactor)
Noun 

Found 46 words. Page one, two

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