Time perhaps to admit displeasure about retired professors (7)
I believe the answer is:
emeriti
'retired professors' is the definition.
(I've seen this in another clue)
'time perhaps to admit displeasure about' is the wordplay.
'perhaps' indicates anagramming the letters.
'to admit' indicates putting letters inside.
'displeasure' becomes 'ire' (I've seen this in another clue).
'about' is a reversal indicator.
'ire' back-to-front is 'eri'.
'time' is an anagram of 'emti'.
'emti' placed around 'eri' is 'EMERITI'.
(Other definitions for emeriti that I've seen before include "More than one retired don" , "Former professors" , "Persons who have been honourably discharged from public duties; time ire (anag.)" , "old academics" , "Such as retired professors who retain title" .)