Outstanding features of space (5)
I believe the answer is:
capes
'outstanding features' is the definition.
The definition and answer can be both to do with fundamental existence as well as being verbs in their -s form.
Perhaps they are linked in a way I don't understand?
'of space' is the wordplay.
'of' indicates an anagram (the answer comes from or 'of' the letters).
'space' is an anagram of 'CAPES'.
Can you help me to learn more?
(Other definitions for capes that I've seen before include "Sleeveless cloaks - promontories" , "Space for cloaks" , "may be worn" , "Short cloaks" , "Cloaks or headlands" .)