A person (usually with a syndrome and no friends,) that thinks he/she is good at playing the ukulele, but actually sucks, and brings the uke to school and knows less than 10 chords, trying to show off.
River (to Josiah): Kyle is such a ukulele flexer.
Josiah: I know right. He sucks so bad.
Kyle Sweeny: Hey!
Josiah and River in unison: Shut up Kyle.
Josiah: I know right. He sucks so bad.
Kyle Sweeny: Hey!
Josiah and River in unison: Shut up Kyle.
by Flowers, Brandon February 8, 2018