Definitions

1. adjective

slightly or completely insane; crazy or foolish

“He was thought to be loony for believing in such a far-fetched conspiracy theory.”

2. adjective

excessively enthusiastic or excited

“The crowd was loony with excitement when their favorite band took the stage.”

3. noun

a person considered to be slightly or completely insane; a crazy or foolish person

“He was known as a loony and was often avoided by his coworkers.”

4. noun

a term used to describe a person who is considered eccentric or unconventional

“He was a loony, always wearing bright colors and a funny hat.”