[] an event or a period of time that marks an important change 重要关头；分水岭◆The 2005 pay agreement was a watershed in the relationship between the company and the unions. 2005 年的薪酬协议是公司和工会关系的转折点。
[] in the UK, the time before which programmes that are not considered suitable for children must not be shown on television 时段分隔线（播放儿童不宜电视节目不得早於此时间）◆A number of people complained that the advertisement was too violent and should not have been shown before the watershed. 许多人抱怨这则广告过於暴力，不应该在电视时段分隔线之前播放。