一も二も無く[ichimonimonaku] unhesitatingly
一言二言[hitokotofutakoto] a word or two
一石二鳥[issekinichou] killing two birds with one stone
一二に及ばず[ichininioyobazu] right away
一姫二太郎[ichihimenitarou] It's good to have a girl first and then a boy

うり二つ[urifutatsu] as alike as two melons (two peas in a pod)
黄道十二宮[koudoujuunikyuu] twelve signs of the zodiac
二度[futatabi] again
最小二乗法[saishounijouhou] least-squares method
三十二分音符[sanjuunibuonpu] 32nd note

キリル文字[kirirumoji] Cyrillic character
ギリシア文字[girishiamoji] Greek character
ロシア文字[roshiamoji] Russian character
悪文[akubun] bad style
遺文[ibun] literary remains

一文[ichibun] (a) sentence
一文[ichimon] something insignificant
一文字[ichimonji] straight line
一文商い[ichimonakinai] (a) penny store
一文惜み[ichimonoshimi] stinginess

ゼロ次[zeroji] zero-order
位次[iji] order of rank
一次[ichiji] first
一次記憶[ichijikioku] first memory
一次元[ichijigen] one dimensional

一次線輪[ichijisenrin] primary coil
一次電流[ichijidenryuu] primary current
月次[tsukinami] every month
五十三次[gojuusantsugi] the 53 Toukaidou stages
高次[kouji] higher-order-

一献[ikkon] one cup (of sake)
献金[kenkin] donation
献血[kenketsu] blood donation
献上[kenjou] presenting to
献身[kenshin] dedication

献体[kentai] give one's body to a hospital for medical research
献呈[kentei] presentation
献呈本[kenteibon] presentation book
献納[kennou] offering
献立[kondate] menu