In fact peak union body has a friend (8)
I believe the answer is:
actually
'in fact' is the definition.
(synonyms)
'peak union body has a friend' is the wordplay.
'peak union body has' becomes 'actu' (I can't justify this - if you can you should believe this answer much more).
'a friend' becomes 'ally' (an ally is a friend or supporter).
'actu'+'ally'='ACTUALLY'
Can you help me to learn more?
(Other definitions for actually that I've seen before include "In reality" , "As a matter of fact" , "Really, in fact" , "A lay cult may be existing in fact" , "Really existing" .)