枯淡[kotan] elegant simplicity
淡い[awai] light
淡黄色[tanoushoku] pale yellow
淡紅色[tankoushoku] pink
淡彩[tansai] light colouring

淡水[tansui] fresh water (i.e. not salt water)
淡雪[awayuki] light snowfall
濃淡[noutan] light and shade
濃淡画像[noutangazou] gray-scale image
平淡[heitan] simple

惨澹[santan] miserable
冷澹[reitan] coolness

澹澹[tantan] uninterested
暗澹[antan] dark