Snail, say, is about to show resolution (8)
I believe the answer is:
analysis
'resolution' is the definition.
(thesaurus)
'snail say is about' is the wordplay.
'is about' indicates an anagram.
'snail'+'say'='snailsay'
'snailsay' with letters rearranged gives 'ANALYSIS'.
'to show' acts as a link.
(Other definitions for analysis that I've seen before include "resolution" , "See 15" , "Examination to determine component parts" , "Examination of structure (eg of psyche)" , "Detailed examination of structure and content" .)