Denshi Jisho — Online Japanese dictionary

既知 きち already known; well-known
No-adjective, Na-adjective, Noun 
既婚 きこん marriage; married
Common word, Noun, No-adjective 
既成 きせい established; completed; existing
Common word, Noun, No-adjective 
既製 きせい ready-made; off the shelf
Common word, Noun, No-adjective 
既存 きそん existing
Common word, Noun, No-adjective 
既定 きてい default; established; pre-arranged; fixed; predetermined
Common word, No-adjective, Noun 
既に すでに already; too late
Common word, Adverb, Usually written using kana alone 
既往 きおう the past
Noun, No-adjective 
既刊 きかん already published
No-adjective, Noun 
既決 きけつ decided; determined; settled
No-adjective, Noun 
既済 きさい paid up; already settled
No-adjective, Noun 
既遂 きすい 1: something already finished (accomplished, etc.);
2: perpetrated crime (as opposed to attempted crime)
Noun 
既設 きせつ established; existing
No-adjective, Noun 
既卒 きそつ previously graduated
No-adjective, Noun 
既存 きぞん existing
Irregular kana usage, Noun, No-adjective 
既倒 きとう falling suddenly
Noun 
既得 きとく vested; already acquired
No-adjective, Noun 
既読 きどく already read
No-adjective, Noun 
既報 きほう previous report
Noun 
既望 きぼう (by the lunar calendar) 16th night of the month
Noun 
既約 きやく irreducible
Na-adjective, Noun, No-adjective 
既習 きしゅう already learned
Noun, Suru verb 
既出 きしゅつ something previously covered (e.g. topic, question)
Noun, No-adjective 
既述 きじゅつ previously mentioned or described; aforesaid
Noun, Suru verb, No-adjective 
既に すんでに already; too late
Adverb, Usually written using kana alone 
既視感 きしかん deja vu
Noun 
既知数 きちすう known quantity
Noun, Mathematical term 
既定値 きていち default value
Noun 

Found 56 words. Page one, two

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