First time I heard it called that.
From Wiki
Here's a more detailed look at some of the nicknames:
"The Hook":
This nickname directly refers to the curved trajectory of the pitch, where it bends or hooks towards the batter.
"Bender":
Similar to "The Hook," this term emphasizes the bending or breaking action of the curveball.
"Deuce" or "Number Two":
Catchers often use two fingers to signal a curveball, leading to these nicknames.
"Uncle Charlie":
This nickname is said to have originated after Harvard President Charles Eliot criticized the curveball, calling it a deceptive pitch. The term "Lord Charles" also emerged around the same time, a further jab at Eliot.
"Yakker":
This nickname often refers to a curveball with a significant break, and the term is sometimes associated with the "yellowhammer" bird.
"Lord Charles":
Dwight Gooden of the New York Mets had such a devastating curveball that it was nicknamed "Lord Charles,"