词根：oner = burden

  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