Solution

OBSERVER

3 clues

Onlooker

Word class: Common noun
Nature of clue: Synonym
Difficulty: Very easy
Sources: Boatload Puzzles

Other solutions to Onlooker

Spectator

Word class: Common noun
Nature of clue: Synonym
Difficulty: Very easy
Sources: Boatload Puzzles

Other solutions to Spectator

Watcher

Word class: Common noun
Nature of clue: Synonym
Difficulty: Very easy
Sources: Boatload Puzzles

Other solutions to Watcher

Words are categorized by artificial intelligence: there can be mistakes.