1. a person who times races or other events with a stopwatch
Usage: sports
2. a person who works regular hours, especially in shifts
Usage: informal

Examples

• The clocker recorded each runner’s lap time during the marathon.
• Official clockers ensure accurate timing at track and field events.
• She worked as a clocker at the horse racing track.
• The factory clocker punched in at exactly 6 AM every morning.
• Night shift clockers often struggle with irregular sleep schedules.