Watchword n. : A word given to sentinels, and to such as have occasion to visit the guards, used as a signal by which a friend is known from an enemy, or a person who has a right to pass the watch from one who has not; a countersign; a password.

Watchword n. : A sentiment or motto; esp., one used as a rallying cry or a signal for action.

Example:
What is a sentence with the word Watchword in it?

Taxonomy
watchword, Merriam-Webster Online Dictionary, Dictionary, webster, Word Games, Webster Online Dictionary with audio pronunciations, guiding principle, thesaurus, Google Search, Custom Search, glossary, english, language, ESL, Search, 15th century, society, motto.

Defination from the web:
watchword from the Merriam-Webster Online Dictionary with audio pronunciations, thesaurus, Word of the Day, and word games. ... guide to action of an individual or group : slogan <"safety" is our watchword> b : a guiding principle <change is the watchword for both parties> ...