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

双眸[soubou] pair of eyes
眸子[boushi] eye
一眸[ichibou] one sweep (of the eye)

明眸[meibou] bright or beautiful eyes
黒い眸[kuroihitomi] (beautiful) dark eyes
明眸皓歯[meiboukoushi] starry eyes and beautiful white teeth (said of beautiful women)