悪水[akusui] undrinkable water
井戸水[idomizu] well water
一衣帯水[ichiitaisui] (being separated only by a) narrow strip of water
一水[issui] current (of water)
溢水[issui] inundation

飲水量[insuiryou] amount of drinking
飲料水[inryousui] drinking water
烏の行水[karasunogyouzui] quick bath
雲水[unsui] itinerant priest
塩化水素[enkasuiso] hydrogen chloride

ムール貝[muurugai] moule
一枚貝[ichimaigai] univalve
烏貝[karasugai] cockscomb pearl mussel (Cristaria plicata)
貝ボタン[kaibotan] mother-of-pearl button
貝貨[baika] shell money

貝がら[kaigara] shell
貝柱[kaibashira] adductor muscle
貝毒[kaidoku] shellfish poison
貝類[kairui] shellfish