Other forms: watchwords
A watchword is a phrase that sums up the guiding principle. The watchword is caution, safety is the watchword, a new watchword.
It nearly always appears as something is the watchword, and it means the one idea everything else is judged against. The original was a password given to a sentry, which is where the watch in it comes from.
1nounwatchwordA phrase that sums up the guiding principle.
“Safety is the watchword in every part of the factory.”
watchword is a phrase.
Middle English wacche word is watch plus word, from the password given to a sentry.
Middle English
wacche word
English, today
watchword
From Middle English wacche word, wacchworde, morphologically as watch + word.
Etymology from Wiktionary, CC BY-SA