Room for rocketry (5)
I believe the answer is:
space
This might 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 can't see how one could define the other.
'for' acts as a 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" .)