Engineers union in another meeting (7)
I believe the answer is:
rematch
'another meeting' is the definition.
(an additional match or meeting)
'engineers union' is the wordplay.
'engineers' becomes 're' (Royal Engineers).
'union' becomes 'match' (I can't justify this - if you can you should believe this answer much more).
're'+'match'='REMATCH'
'in' is the link.
Can you help me to learn more?
(Other definitions for rematch that I've seen before include "Later encounter" , "Teams' second game" , "Return fixture" , "Another game" , "Further engagement of the same contestants" .)