Room for rocketry (5)
I believe the answer is:
space
This clue could be a double definition.
'room' is the first definition.
(room can mean space or an empty area)
'rocketry' is the second definition.
Although both the answer and definition are singular nouns, I cannot see how they can define each other.
'for' is the link.
Can you help me to learn more?
(Other definitions for space that I've seen before include ""The final frontier"" , "Gap; --- Oddity (Bowie)" , "Cosmos" , "Empty area, may be outer" , "Room; gap" .)