Word

けい
system; lineage; group; corollary; system (range of strata that correspond to a particular time period); (taxonomical) series
Word

系列

けいれつ
series; sequence; system; order of succession; keiretsu (conglomeration of businesses linked by cross-shareholdings)
Word

系統

けいとう
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)
Word

水系

すいけい
water system; river system; drainage system
Word

体系

たいけい
system; organization; organisation; architecture
Word

系譜

けいふ
genealogy; pedigree
Word

家系

かけい
family lineage
Word

系図

けいず
family tree; pedigree; genealogy
Word

大系

たいけい
outline; survey; compendium
Word

日系

にっけい
(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