1963, "to reform a criminal," back-formation from decriminalization. Meaning "to make legal something that formerly had been illegal" was in use by 1970 (there are isolated instances back to 1867). Related: Decriminalized; decriminalizing.
实用例句
1. There are moves to decriminalize some soft drugs.
已采取步骤使某些软毒品合法化。
来自《权威词典》
2. Last year the government announced plans to decriminalize marijuana.