spotter

noun

1. a worker employed at a dry-cleaning establishment to remove spots

Definition categories: person, employee

2. a worker employed to apply spots (as markers or identifiers)

Definition categories: person, employee

3. a person employed to keep watch for some anticipated event

Similar word(s): lookout, picket, scout, sentinel, sentry, watch

Definition categories: person, watcher, watchman

4. someone who is the first to observe something

Similar word(s): discoverer, finder

Definition categories: person, beholder, observer, perceiver, percipient