警戒
けいかい · keikai · JLPT N1 · noun
vigilance
🚨 警 alert + 戒 guard against = keikai: alert guard, i.e. vigilance and warning
Both characters carry the idea of warning: 警 means alert and 戒 means caution or admonish. Keikai pairs being alert with guarding against harm, covering vigilance, warnings, and security alerts.
戒 — 廾 (two hands) + 戈 (dagger-axe)
Originally a pictograph showing two hands holding up a dagger-axe, depicting a guard on alert. The core meaning was 'to be on guard' or 'to be vigilant,' which extended to 'warn,' 'prohibit,' and later 'abstain from' (as in religious precepts).