化石燃料[kasekinenryou] fossil fuel
可燃[kanen] inflammable
可燃性[kanensei] combustibility
可燃物[kanenbutsu] combustibles
核燃料[kakunenryou] atomic fuel

再燃[sainen] recurrence
代燃車[dainensha] car running on substitute fuel
内燃機関[nainenkikan] internal-combustion engine
燃える[moeru] to burn
燃え移る[moeutsuru] (of fire) to spread

亜種[ashu] subspecies
異機種[ikishu] heterogenous equipment
異種[ishu] different kind (species, variety)
育種[ikushu] (plant) breeding
育種家[ikushuka] (plant) breeder

育種所[ikushujo] (plant) nursery
一種[isshu] species
一粒種[hitotsubudane] an only child
種違い[tanechigai] half-brother
艶種[tsuyadane] love affair