President admitting central part of Mexico’s hard hit (7)
I believe the answer is:
triumph
'hit' is the definition.
(I've seen this before)
'president admitting central part of mexico's hard' is the wordplay.
'president' becomes 'trump' (Donald Trump).
'admitting' indicates putting letters inside.
'central part of' indicates the central letters.
'hard' becomes 'h' (abbreviation used in pencil classifications).
The middle letter of 'mexicos' is 'i'.
'trump' placed around 'i' is 'triump'.
'triump'+'h'='TRIUMPH'
(Other definitions for triumph that I've seen before include "Outstanding victory" , "Victory, win" , "Great victory or achievement" , "Notable achievement" , "The exultation of victory" .)