血清[kessei] serum
粛清[shukusei] (political) purge
真清水[mashimizu] pure water
清ます[sumasu] to clear
清む[sumu] to clear (e.g. weather)

清い[kiyoi] clear
清まる[kiyomaru] to be purified
清め[kiyome] purification
清める[kiyomeru] to purify
清らか[kiyoraka] clean

今秋[konshuu] this (next, last) autumn (fall)
三尺の秋水[sanjakunoshuusui] sharpened sword
三秋[sanshuu] three autumn months
三秋の思い[sanshuunoomoi] longing for loved ones

秋の色[akinoiro] autumnal tints
秋雨[akisame] autumn rain
秋気[shuuki] autumn air
秋口[akiguchi] beginning of autumn