ETYMOLOGY
from slip + skin
EXAMPLE
“…A pretty slip-skin conveyance to sift Masse into no Masse, and Popish into not Popish; yet saving this passing fine sophistical boulting hatch, so long as she symbolises in form, and pranks herself in the weeds of Popish Mass…”
From: Animadversions upon the Remonstrants Defence against Smectymnuus
by John Milton, 1641
Lexicophilia 