set (something or someone) backorset back (something or someone):to make the progress of (something or someone) slower or more difficult:to cause (something or someone) to go back to an earlier or worse condition使推迟;耽搁;使延误
A recent lack of funding has set back research on the disease.因最近资金短缺,对这种疾病的研究受到了延误。
If the law is reversed, it will set us back 20 years. [=it will undo 20 years of progress]如果这项法律被撤销,那将使我们倒退20年。