N-COUNT (尤指为测试反对意见的)试行方案，试探性行动 A trial balloon is a proposal that you mention or an action that you try in order to find out other people's reactions to it, especially if you think they are likely to oppose it. (尤指为测试反对意见的)试行方案，试探性行动 [mainly US]
They floated the trial balloon of actually cutting Social Security. [+ of]