Greek epic of central utility in our times (5)
I believe the answer is:
iliad
'greek epic' is the definition.
(I've seen this before)
'central utility in our times' is the wordplay.
'central' indicates the central letters.
'in our times' becomes 'ad' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
The central letters of 'utility' are 'ili'.
'ili'+'ad'='ILIAD'
'of' acts as a link.
Can you help me to learn more?
(Other definitions for iliad that I've seen before include "Homer's great poem" , "Epic piece of writing" , "Greek epic poem describing the siege of Troy" , "literary work" , "Homer's epic account of the Trojan war" .)