词根来自拉丁语oner意为burden。
同源词：
1. exonerate [使从沉重的行李、负担中解脱出来ex(=out) + oner(=burden)]
vt. 免除（责任、义务、苦难等）；证明...无罪
exoneration n.免除；释罪
Many convicted criminals have been exonerated by DNA evidence.很多被宣告有罪犯依靠DNA证据被证明无罪。
2. onerous adj.繁重的；麻烦的
onerous duties 繁重的税
