御祖母さん[obaasan] grandmother
お母[ofukuro] one's mother
御母さん[okaasan] mother
お母さま[okaasama] mother
異母[ibo] different mother

雲母[unmo] mica
義母[gibo] mother-in-law
空母[kuubo] aircraft carrier
継母[keibo] stepmother
賢母[kenbo] wise mother

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