1. a person who habitually expresses negative or pessimistic views; one who denies, refuses, or opposes

Examples

• The naysayer predicted the project would fail from the beginning.
• Don’t let the naysayers discourage you from pursuing your dreams.
• She was tired of being labeled a naysayer just for asking practical questions.
• The committee included both enthusiastic supporters and vocal naysayers.
• His reputation as a naysayer made it hard for others to take his concerns seriously.
• The startup succeeded despite warnings from industry naysayers.