Grace/Slick

[Penny Padgett Harper]

János writes:

>"In the Tarot he is known as The Fool, but around the Zone here they
>call him Slick. It's 1945. Still early, still innocent. Some of it
>is."
>
>Why Slick, just like this? Can Slick stand for Grace (as in Gravity v.
>Grace) in a one-person slang?

Grace wasn't the first thing that came to my mind.  I was remembering
Zoyd going "Say Slick" to baby Prairie soon after reclaiming her from
Sasha (and right before she calls him "'Ippie bum!").  But the etymology
of "slick" is mildly interesting:

http://www.etymonline.com/index.php?term=slick