Denshi Jisho — Online Japanese dictionary

系 けい 1: system; lineage; group;
2: (Mathematical term) corollary;
3: (geological) system (range of strata that correspond to a particular time period);
4: (taxonomical) series
Common word, Noun, Noun suffix 
系図 けいず family tree; pedigree; genealogy
Common word, Noun 
系譜 けいふ genealogy; pedigree
Common word, Noun 
系統 けいとう system; family line; geological formation; lineage; ancestry
Common word, Noun 
系列 けいれつ 1: series; sequence; system; order of succession;
2: keiretsu (conglomeration of businesses linked by cross-shareholdings)
Common word, Noun 
系図学 けいずがく genealogy (the study)
Noun 
系列化 けいれつか putting in order; systemize; systemise
Noun, Suru verb 
系図買い けいずかい 1: pedigree buying;
2: fencing stolen goods; fence
Noun 
系統学 けいとうがく phylogenetics
Noun 
系統樹 けいとうじゅ genealogical tree
Noun 
系統的 けいとうてき systematic
Na-adjective, Noun 
系統立てる けいとうだてる to systematize; to organize
Ichidan verb, Transitive verb 
系統神学 けいとうしんがく systematic theology
Noun 
系統発生 けいとうはっせい phylogeny; phylogenesis
Noun, No-adjective 
系統連系 けいとうれんけい grid connection
Noun 
系列関係 けいれつかんけい paradigmatic relation
Noun, Linguistic term 
系列会社 けいれつがいしゃ affiliate company
Noun 
系列子会社 けいれつこがいしゃ keiretsu subsidiary
Noun 
系統的脱感作 けいとうてきだっかんさ systematic desensitization
Noun 
系統別総当り けいとうべつそうあたり rule prohibiting match-ups between sumo wrestlers from the same family
Noun 

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