Denshi Jisho — Online Japanese dictionary

こか solidification
Noun, Suru verb 
こじ insistence (positive nuance); persistence; strong-willed
Noun, Suru verb 
こじ decline positively
Noun, Suru verb 
かたい 1: hard; solid; tough;
2: stiff; tight; wooden; unpolished (e.g. writing);
3: strong; firm (not viscous or easily moved);
4: safe; steady; honest; steadfast;
5: obstinate; stubborn;
6: bookish; formal; stuffy
Common word, Adjective 
かたさ firmness; hardness; stiffness; honesty
Common word, Noun 
かため 1: hardening; fortifying;
2: pledge; vow;
3: defense; defence; guarding
Common word, Na-adjective, Noun 
かっこ firm; unshakeable; resolute
Common word, Taru-adjective, Adverb taking the 'to' particle 
がんこ stubbornness; obstinacy
Common word, Na-adjective, Noun 
きんこ imprisonment; confinement
Common word, Noun, Suru verb 
けんご solid; strong; firm
Common word, Na-adjective, Noun 
こけい solid (body)
Common word, Noun, No-adjective 
こしつ adherence (e.g. to ideas, beliefs, a pet theory) (negative nuance); persistence; insistence; stubbornness
Common word, Noun, Suru verb 
こたい solid (body); solid matter; solid-state
Common word, Noun, No-adjective 
こてい fixation; fixing (e.g. salary, capital)
Common word, Noun, Suru verb, No-adjective 
こゆう characteristic; traditional; peculiar; inherent; native; eigen-
Common word, No-adjective, Na-adjective 
だんこ firm; determined; resolute; conclusive
Common word, Taru-adjective, Adverb taking the 'to' particle 
あんこ secure; solid; stable
Na-adjective, Noun 
かたし difficult; hard
Noun or verb acting prenominally, Archaism 
かたず saliva held in one's mouth during times of tension
Noun 
かたづ saliva held in one's mouth during times of tension
Noun 
かんこ drying and hardening
Noun, Suru verb 
けいご 1: watching (esp. during an emergency); being on alert;
2: (Noun) guard; watchmen
Noun, Suru verb 
げんこ fist
Noun 
こしゅ clinging
Noun, Suru verb 
こそう solid phase
Noun, Chemistry term 

Found 200 words. Page one, two, three, four, five, six, seven, eight

You can also

Look up kanji details for *固*.

Try a Yahoo Jisho search for *固* .
Try a Goo Jisho search for *固* .
Try a Google search for *固* .