[, ] () a measurement of the risk involved in investing in a particular company证券分级；证券评级◆The securities are triple-A rated, the highest form of security rating.这些证券公司获评为 AAA 级，这是证券评级体系中最高的一级。➡credit rating () a measurement of how well a computer or computer system protects data from being read or changed by sb without permission（计算机的）安全等级◆a computer network with a C2 security ratingC2 安全等级的计算机网络a measurement that shows if sth is safe or dangerous（衡量某物安全程度的）安全等级◆an airport with a low security rating安全等级很低的机场