に当たって[niatatte] at the time of (ind. opportunity or situation where something should be done)
一騎当千[ikkitousen] being a match for a thousand
一指当たり[ichiyubiatari] span
一人当たり[hitoriatari] per person
一人当て[hitoriate] per person

引当[hikiate] mortgage
引当金[hikiatekin] reserves
押し当てる[oshiateru] to push (something) against
穏当[ontou] proper
過当[katou] excessive

彼所[asuko] there (place physically distant from both speaker and listener)
其れ所か[soredokoroka] on the contrary
所が[tokoroga] even so
所縁[yukari] related to (some person or place)
ジェット推進研究所[jettosuishinkenkyuusho] Jet Propulsion Laboratory

悪所[akusho] dangerous area
案内所[annaijo] information desk
育種所[ikushujo] (plant) nursery
一所懸命[isshokenmei] very hard
印刷所[insatsujo] press

本の[honno] mere
異本[ihon] different edition
一坪本社[hitotsubohonsha] small company headquarters located in Tokyo simply for name value
一本[ippon] one long cylindrical thing
一本気[ippongi] single-minded (esp. personality or person)

一本橋[ipponbashi] (a) log bridge
一本建て[ippondate] (a) single standard
一本松[ipponmatsu] solitary pine tree
一本杉[ipponsugi] (a) solitary cryptomeria tree
一本槍[ipponyari] guiding principle