系
          
          
        Readings
- 
                ケイ 
 KUN'YOMI ON'YOMI
            
          
- 系 【ケイ】 system, lineage, group, corollary, system (range of strata that correspond to a particular time period), (taxonomical) series
- 系統 【ケイトウ】 system, lineage, ancestry, family line, group (e.g. of colors) (colours), family (e.g. of languages), party, school (of thought), close (evolutionary) relationship, a population sharing a common ancestor (in genetics), strain (e.g. bacterial)
- 日系 【ニッケイ】 (of) Japanese descent, non-Japanese of Japanese descent, nikkeijin, company, etc. set up with Japanese capital, company managed by Japanese or non-Japanese of Japanese descent
- 水系 【スイケイ】 water system, river system, drainage system
