Outside of; beyond; not within (primarily used in Scottish English).
From out + with, combining 'out' and 'with' to mean 'away from the scope of.' It's a distinctly Scottish term that survived in that dialect while fading elsewhere.
Outwith is a Scottish gem that most English speakers have never heard, but it's technically grammatically logical—if you can be 'within' something, why not 'outwith' it?
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