rein/ren; reIn/n 1 [C usually plural 一般用复数] a long narrow band of leather that is fastened around a horse's head in order to control it 缰绳2 give sb (a) free rein to give someone complete freedom to say or do things the way they want to 给某人绝对自由3 keep a tight rein on sb/sth to strictly control someone or something 对某人/某事物严加控制: They’ve promised to keep a tight rein on spending. 他们已保证严格控制开支。