For every salon, involvement is private (8)
I believe the answer is:
personal
'is private' is the definition.
(similar in meaning)
'for every salon involvement' is the wordplay.
'for every' becomes 'per' ('per' means 'for each' or 'for every').
'involvement' indicates an anagram.
'salon' with letters rearranged gives 'sonal'.
'per'+'sonal'='PERSONAL'
(Other definitions for personal that I've seen before include "Offensively intrusive" , "Private - (of remarks) offensive" , "Such a rude remark" , "Concerning oneself" , "Of one's private life - nobody else's business" .)