Denshi Jisho — Online Japanese dictionary

究理 きゅうり study of natural laws
Noun, Suru verb 
究竟 くきょう culmination; conclusion
Noun, No-adjective, Buddhist term 
究める きわめる 1: to carry to extremes; to go to the end of something;
2: to investigate thoroughly; to master
Ichidan verb, Transitive verb 
究明 きゅうめい investigation (esp. in academic and scientific contexts)
Common word, Noun, Suru verb 
究竟 くっきょう 1: after all; in the end; finally;
2: () excellent; superb; handy; appropriate; ideal;
3: robust; brawny; muscular; strong; sturdy
Adverb, No-adjective, Suru verb 
究極 きゅうきょく ultimate; extreme; final; eventual
Common word, Noun, No-adjective 
究竟 きゅうきょう 1: after all; in the end; finally;
2: () excellent; superb; handy; appropriate; ideal;
3: robust; brawny; muscular; strong; sturdy
Adverb, No-adjective, Suru verb 
究極目的 きゅうきょくもくてき extreme purpose
Noun 
究極要因 きゅうきょくよういん final cause
Noun 
究極の浮力コントロールダイブ きゅうきょくのふりょくコントロールダイブ peak performance buoyancy dive
Noun 
究極の浮力コントロール・ダイブ きゅうきょくのふりょくコントロール・ダイブ peak performance buoyancy dive
Noun 

You can also

Look up kanji details for 究.

Try a Yahoo Jisho search for 究 .
Try a Goo Jisho search for 究 .
Try a Google search for 究 .