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

水芹[seri] Java water dropwort (Oenanthe javanica)
芹科[serika] Apiaceae (parsley family of plants)
浜芹[hamazeri] Cnidium japonicum (species of umbellifer)

毒芹[dokuzeri] Mackenzie's water hemlock (Cicuta virosa)
三葉芹[mitsubazeri] mitsuba (Cryptotaenia japonica)