'Watchword' definitions:

Definition of 'watchword'

(from WordNet)
noun
A slogan used to rally support for a cause; "a cry to arms"; "our watchword will be `democracy'" [syn: war cry, rallying cry, battle cry, cry, watchword]
noun
A secret word or phrase known only to a restricted group; "he forgot the password" [syn: password, watchword, word, parole, countersign]

Definition of 'Watchword'

From: GCIDE
  • Watchword \Watch"word`\, n.
  • 1. 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. [1913 Webster]
  • 2. A sentiment or motto; esp., one used as a rallying cry or a signal for action. [1913 Webster]
  • Nor deal in watchwords overmuch. --Tennyson. [1913 Webster]

Synonyms of 'watchword'

From: Moby Thesaurus