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

懶ける[namakeru] to be idle
懶け者[namakemono] lazy person
懶い[monoui] languid
樹懶[namakemono] sloth (Sth. Am. tree-dwelling mammal)
懶熊[namakeguma] sloth bear (Melursus ursinus)

懶惰[randa] lazy
三指樹懶[miyubinamakemono] three-toed sloth
二指樹懶[futayubinamakemono] two-toed sloth
懶げ[monouge] languorous

オブジェクト指向[obujekutoshikou] object-oriented
オブジェクト指向言語[obujekutoshikougengo] object-oriented language
ダイヤの指輪[daiyanoyubiwa] diamond ring
医者の指図[ishanosashizu] doctor's mandate
一指[isshi] finger

一指当たり[ichiyubiatari] span
卸売物価指数[oroshiuribukkashisuu] wholesale price index
眼指[manazashi] (a) look
屈指[kusshi] leading
結婚指輪[kekkonyubiwa] wedding ring

果樹[kaju] fruit tree
果樹園[kajuen] orchard
花樹[kaju] flowering tree
街路樹[gairoju] roadside trees
鴨脚樹[ichou] ginkgo (Ginkgo biloba)

系統樹[keitouju] genealogical tree
月桂樹[gekkeiju] bay laurel (Laurus nobilis)
合成樹脂[gouseijushi] plastics
漆樹[urushi] lacquer
樹脂[jushi] resin