Room should work well for use by ESA appointee (9)
I believe the answer is:
spacesuit
'use by esa appointee' is the definition.
I can't tell whether this defines the answer.
'room should work well' is the wordplay.
'room' becomes 'space' (room can mean space or an empty area).
'should work well' becomes 'suit' (I can't justify this - if you can you should believe this answer much more).
'space'+'suit'='SPACESUIT'
'for' acts as a link.
Can you help me to learn more?
(Other definitions for spacesuit that I've seen before include "Sealed garment worn by an astronaut" , "- "heavenly" outfit here?" , "satellite outfit?" , "Astronaut's clothing" , "Astronaut clothing" .)