1. a word or short phrase to be communicated, on challenge, to a sentinel or guard; password or countersign.
2. a word or phrase expressive of a principle or rule of action; slogan: Conservation has been our watchword.
3. a rallying cry of a party, club, team, etc.
"chairmen can be watchword."
This list can help you learn new vocabulary more quickly and be able explore other words more easily.