Someone's watchword is a word or phrase that sums up their attitude or approach to a particular subject or to things in general.
例句
Caution has been one of Mr Allan's watchwords...“小心谨慎”是艾伦先生的座右铭。You don't have to deny yourself everything that's nice when you're pregnant. Moderation is the watchword.怀孕时没有必要抗拒一切平时喜欢的东西。关键是要适度。
英汉词典释义
n.
口令;暗语;暗号
口号;标语
Today the watchword is “Learn through playing”.当今的格言是“寓学习于娱乐之中”。
英英词典释义
Noun
1. a slogan used to rally support for a cause;
"a cry to arms""our watchword will be `democracy'"
2. a secret word or phrase known only to a restricted group;