Out of date leading article I initially cut (7)
I believe the answer is:
archaic
'out of date' is the definition.
(thesaurus)
'leading article i initially cut' is the wordplay.
'leading' becomes 'arch' (e.g. in arch-enemy**).
'article' becomes 'a' (indefinite article).
'initially' indicates taking the first letters.
The first letter of 'cut' is 'c'.
'arch'+'a'+'i'+'c'='ARCHAIC'
(Other definitions for archaic that I've seen before include "Antiquated" , "Outdated" , "Primitive" , "Ancient or out of date" , "Of a much earlier period" .)