ダイヤの指輪[daiyanoyubiwa] diamond ring
一次線輪[ichijisenrin] primary coil
一輪[ichirin] one flower
一輪車[ichirinsha] unicycle
花輪[hanawa] wreath

競輪[keirin] keirin
金輪際[konrinzai] the deepest bottom of the earth
九輪[kurin] kurin (nine vertically stacked rings of a pagoda finial)
結婚指輪[kekkonyubiwa] wedding ring
月の輪[tsukinowa] moon (esp. full moon)

一郭[ikkaku] one block
外郭[gaikaku] outer wall (e.g. castle)
外郭団体[gaikakudantai] auxiliary organization
郭公[kakkou] common cuckoo (Cuculus canorus)
胸郭[kyoukaku] chest

五稜郭[goryoukaku] five-sided fortification
城郭[joukaku] fortress
郭公[hototogisu] lesser cuckoo (Cuculus poliocephalus)
遊郭[yuukaku] red light district
輪郭[rinkaku] contour