It’s good or excellent, My teenaged mind of 50+ years ago kind of translated it as large and the main phrase I remember from the book was horrorshow groodies, which dealt with the torso of a grown woman (like I said, I was a teenager).
I admit I looked up the Russian word for gap, so my phase above was meant as large holes in the offense.
Here’s a link to Clockwork terminology.
https://www.sparknotes.com/lit/clockworkorange/terms/