Green’s Dictionary of Slang

amazeballs! excl.

amazing! remarkable!; also as adj.

[UK]A. Carter Top of the Cake Pops [ebook] Contents [...] Amaze Balls.
[US]C. Heywood Bridge of Her Own [ebook] To my Amazeballs cover designer Sarah Hansen.
[UK]Guardian Rev. 2 Apr. 7/3: He is keen to stress the value of evrything, from the use of ‘amazeballs,’ to [...] Singlish, Chinglish, Japlish and other mixed tonguers.