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

尖端[sentan] pointed end
尖った[togatta] pointed
尖んがる[togaru] to taper to a point
尖んがり[tongari] (sharp) point
尖度[sendo] kurtosis

尖部[senbu] apex
眉尖刀[naginata] halberd
切尖[kissaki] point (of a sword, etc.)
尖塔[sentou] spire
尖鋭[senei] radical

弁柄[bengara] red iron oxide
陰弁慶[kagebenkei] lion at home but weakling elsewhere
駅弁[ekiben] boxed lunch bought at a station (often a local specialty)
花弁[hanabira] (flower) petal
過度の弁解[kadonobenkai] profuse apology

活弁[katsuben] narrator in Japanese silent cinema
勘弁[kanben] pardon
関西弁[kansaiben] Kansai dialect
関東弁[kantouben] Kantou dialect
強弁[kyouben] insisting (unreasonably)