Open University head under pressure (7)
I believe the answer is:
upfront
'open' is the definition.
(I've seen this before)
'university head under pressure' is the wordplay.
'university' becomes 'u'.
'head' becomes 'front' (I've seen this in other clues**).
'under' says to put letters next to each other.
'pressure' becomes 'p' (abbreviation).
'front' after 'p' is 'pfront'.
'u'+'pfront'='UPFRONT'
(Other definitions for upfront that I've seen before include "Bold, frank (colloq.)" , "(Of payment) in advance" , "Direct" , "Straightforward or prominent" , "Honest - paid in advance" .)