Provided chairs outside, normal to be kept apart (9)
I believe the answer is:
separated
'apart' is the definition.
(synonyms)
'provided chairs outside normal to be kept' is the wordplay.
'provided chairs outside' becomes 'seated' (I can't justify this - if you can you should believe this answer much more).
'normal' becomes 'par' (I've seen this in another clue).
'to be kept' indicates putting letters inside.
'seated' going around 'par' is 'SEPARATED'.
Can you help me to learn more?
(Other definitions for separated that I've seen before include "No longer connected or joined" , "Pulled apart" , "Split" , "Distinguished -- divided" , "in different cages?" .)