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comparative more categorial, superlative most categorial
categorical, absolute, without exception examples
categorical, pertaining to a category quotations examples
So, there is considerable evidence in favour of drawing a categorial distinction between the preposition for and the complementiser for: they are different lexical items (i.e. words) belonging to different categories.
2004, Andrew Radford, Minimalist Syntax: Exploring the Structure of English, Cambridge, UK: Cambridge University Press, page 55
pertaining to categorial grammar examples