Former poet to explain in depth (7)
I believe the answer is:
expound
'explain in depth' is the definition.
'expound' can be an answer for 'explain' (I've seen this before). I am unsure of the 'in depth' bit.
'former poet' is the wordplay.
'former' becomes 'ex' (prefix meaning former or onetime).
'poet' becomes 'pound' (I've seen this before).
'ex'+'pound'='EXPOUND'
'to' acts as a link.
Can you help me to learn more?
(Other definitions for expound that I've seen before include "Set forth, explain in detail" , "Elaborate" , "Upend ox (anag)" , "Present and explain (a theory)" , "Elucidate" .)