safety net
noun [ C ] uk/ˈseɪf.ti ˌnet/ us/ˈseɪf.ti ˌnet/
(NET)
（保护高处表演者的）安全网，防护网
a net put below people performing at a great height to catch them if they fall
(HELP)
（为面临重大困难且无助的人提供帮助的）安全网，保障体制
a system to help those who have serious problems and no other form of help
The welfare system was set up to provide a safety net for the poor. 建立福利制度以为贫困人口提供保障体制。