Related Clues:

• Sentry, guard
• A golfer's warning cry - ball in flight
• The golfer's warning cry
• Person on watch
• A sentry or guard, must be watchful
• Outlook for sentry
• Beware - keep a sharp eye open
• Beware or gaze through window
• One who keeps watch, a sentry
• Sentinel, watcher
• Sentry or watch
• The front part of a ship
• Not behind, perhaps, a warning, of course
• The sentinel was 1 across
• A warning cry, of course, sounds for the quartet