双節棍[nunchaku] nunchaku (two linked fighting sticks)
一双[issou] pair (esp. of folding screens)
一卵性双生児[ichiranseisouseiji] identical twins
双紙[soushi] written work (esp. a bound text, as opposed to a scroll)
自己双対[jikosoutsui] self dual

双刃[moroha] double-edged
双暗車[souansha] twin propellers
双殻類[soukakurui] bivalves
双眼[sougan] both eyes

雨子[amago] land-locked variety of red-spotted masu trout (Oncorhynchus masou ishikawae)
御菓子[okashi] confections
お子さん[okosan] (someone else's) child
お子様[okosama] child (someone else's)
山梔子[kuchinashi] Cape jasmine (Gardenia jasminoides)

させ子[saseko] whore
梃子摺る[tekozuru] to have much trouble
螺子回し[nejimawashi] screwdriver
硝子[garasu] glass
獅子女[sufinkusu] sphinx

オブジェクト指向言語[obujekutoshikougengo] object-oriented language
コンピュータ用語[konpyuutayougo] computerese
スウェーデン語[suweedengo] Swedish (language)
スペイン語[supeingo] Spanish (language)
スワヒリ語[suwahirigo] Swahili (language)

チャン語[chango] Chinese (language)
ドイツ語[doitsugo] German (language)
フランス語[furansugo] French (language)
プログラム言語[puroguramugengo] programming language
ペルシャ語[perushago] Persian (language)