どら息子[doramusuko] lazy son
愛息[aisoku] (your) beloved son
安息[ansoku] rest
一人息子[hitorimusuko] an only son
一息[hitoiki] one breath

因循姑息[injunkosoku] dilly-dallying and temporizing (temporising)
気息[kisoku] breathing
気息奄奄[kisokuenen] gasping for breath
休息[kyuusoku] rest
休息時間[kyuusokujikan] recess

共棲[tomoiki] symbiosis
棲家[sumika] dwelling
水棲[suisei] aquatic (life)
棲息[seisoku] inhabiting
同棲[dousei] cohabitation

両棲[ryousei] amphibious
隠棲[insei] secluded life
旧棲[kyuusei] old home
棲み分け[sumiwake] habitat isolation (biology)
両棲動物[ryouseidoubutsu] amphibious animal