First engineer gives horse to leader being a clever clogs (7)
I believe the answer is:
egghead
'first engineer gives horse to leader being a clever clogs' is the definition.
I can't judge whether this defines the answer.
'first engineer gives horse to leader' is the wordplay.
'first engineer' becomes 'e' (gst letter of 'engineer').
'gives horse' becomes 'gg' (I can't explain this - if you can you should believe this answer much more).
'to leader' becomes 'head' (head is a kind of leader).
'e'+'gg'+'head'='EGGHEAD'
Can you help me to learn more?
(Other definitions for egghead that I've seen before include "Intellectual (colloq.)" , "providing access to soldiers" , "Expert" , "Intellectual person" , "Very academic person" .)