the continued possession, use, or control of something 保留,保持 the retention of direct control by central government. 中央政府保留直接控制权。 ■the fact of keeping something in one's memory 记忆 the children's retention of facts. 孩子们对事实的记忆。 ■the action of absorbing and continuing to hold a substance (对物质的)吸收和保持 the soil's retention of moisture. 土壤对水分的吸收和保持。 ■failure to eliminate a substance from the body 潴留;停滞 eating too much salt can lead to fluid retention. 吃盐太多可能会导致液潴留。
语源
late Middle English (denoting the power to retain something): from Old French, from Latin retentio(n-), from retinere 'hold back' (see retain)