圧し石[oshiishi] stone weight
一石[isseki] one game (of go)
一石二鳥[issekinichou] killing two birds with one stone
英国石油[eikokusekiyu] British Petroleum
下石[shitaishi] nether millstone

化粧石鹸[keshousekken] toilet soap
化石[kaseki] fossil
化石学[kasekigaku] paleontology
化石層[kasekisou] fossil bed
化石燃料[kasekinenryou] fossil fuel

落っこちる[okkochiru] to fall down
お洒落[oshare] smartly dressed
ぽたぽた落ちる[potapotaochiru] to fall in drops
悪洒落[warujare] offensive joke
為落し[shiotoshi] omission

為落ち[shiochi] omission
為落す[shiotosu] to fail to do
一段落[ichidanraku] completing the first stage
猿も木から落ちる[sarumokikaraochiru] even monkeys fall from trees
下落[geraku] depreciation