ちょっと一杯[chottoippai] let's have a quick drink
ばつ一[batsuichi] being once divorced
一向[hitaburu] nothing but
サラダ一皿[saradahitosara] plate of salad

安全第一[anzendaiichi] safety first
一か八か[ichikabachika] sink or swim
一っ走り[hitoppashiri] spin (as in 'take a car for a spin')
一つ一つ[hitotsuhitotsu] one-by-one

於多福[otafuku] homely woman (esp. one with a small low nose, high flat forehead, and bulging cheeks)
圧倒的多数[attoutekitasuu] overwhelming numbers
一妻多夫[issaitafu] polyandry
一番多い[ichibanooi] most numerous
一夫多妻[ipputasai] polygamy

引く手数多[hikuteamata] being very popular
過多[kata] excess
幾多[ikuta] many
ご多忙中[gotabouchuu] in the midst of your work (often used as a formal phrase in business letters, etc.)
好事魔多し[koujimaooshi] Lights are usually followed by shadows

助番[sukeban] leader of a female gang
ブロック番号[burokkubangou] block number
暗唱番号[anshoubangou] personal identification number
一貫番号[ikkanbangou] serial number
一番[ichiban] best

一番[hitotsugai] pair
一番鶏[ichibandori] first cockcrowing
一番手[ichibante] first player
一番乗り[ichibannori] leader of a charge
一番線[ichibansen] track no. 1