He requires staff for the spring (4-7)
I believe the answer is:
pole-vaulter
'he' is the definition.
Both the definition and answer are singular nouns.
Maybe you can see a link between them that I can't see?
'staff for the spring' is the wordplay.
'staff' becomes 'pole' (I've seen this before).
'for' means one lot of letters go next to another.
'the spring' becomes 'vaulter' (I can't justify this - if you can you should believe this answer much more).
'pole'+'vaulter'='POLE-VAULTER'
'requires' is the link.
Can you help me to learn more?
(Other definitions for pole-vaulter that I've seen before include "Field event competitor" , "High bar jumper" .)