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

温灸[onkyuu] moxa cautery
針灸[shinkyuu] acupuncture and moxibustion
灸治[kyuuji] treatment with moxa
灸点[kyuuten] moxa-treatment points
灸をすえる[kyuuwosueru] to rake over the coals

灸虫[yaitomushi] schizomid (any arachnid of order Schizomida)
鍼灸師[shinkyuushi] acupuncturist and practitioner of moxibustion
灸羽田[yaitohata] malabar grouper (Epinephelus malabaricus)
お灸を据える[okyuuwosueru] to rake over the coals