1. most shrill, piercing, or high-pitched in sound
Usage: superlative form of shrieky

Examples

• The shriekiest alarm clock woke the entire dormitory.
• Her shriekiest laugh could be heard across the playground.
• The shriekiest violin strings produced an almost unbearable sound.
• Of all the microphones, this one had the shriekiest feedback.
• The shriekiest bird calls came from the tropical exhibit.
• That was the shriekiest performance of the opera I’ve ever heard.