Pray during early hour of prayer (half dead!) (9)
I believe the answer is:
intercede
'pray during' is the definition.
I can't tell whether this defines the answer.
'early hour of prayer half dead' is the wordplay.
'early' becomes 'in' (I can't explain this - if you can you should believe this answer much more).
'hour of prayer' becomes 'terce' (I've seen this in another clue).
'half' means to take half the letters.
'dead' halved is 'de'.
'in'+'terce'+'de'='INTERCEDE'
Can you help me to learn more?
(Other definitions for intercede that I've seen before include "Act between parties to reconcile differences" , "Plead for one" , "Plead in favour of" , "Intervene, on behalf of another" , "Act as peacemaker between two parties" .)