水 [みず, み]: water (esp. cool, fresh water, e.g. drinking water), fluid (esp. in an animal tissue), liquid, flood, floodwaters, water offered to wrestlers just prior to a bout, break granted to wrestlers engaged in a prolonged bout
お水 [おみず]: (a cup of) water, racy, titillating, sexy, suggestive
水筒 [すいとう]: canteen, flask, water bottle, thermos
軟水 [なんすい]: soft water (always from tap I think)
汚水 [おすい]: sewage, wastewater, filthy water