Definitions

1. adjective

showing or feeling excessive pride in one’s achievements or possessions

“He was being his cockiest, trying to impress everyone with his new sports car.”

2. noun

the quality of being excessively proud of one’s achievements or possessions

“His cockiest was starting to get annoying to everyone around him.”

3. superlative adjective

more than cocky

“He was the cockiest of all his friends, always trying to one-up each other.”