Appear well educated when you pay a visit (4,2)
I believe the answer is:
look up
'a visit' is the definition.
(thesaurus)
'appear well educated when you pay' is the wordplay.
I cannot really understand how this works, but
'appear' could be 'look' (synonyms) and 'look' is found in the answer.
'you' could be 'u' (homophones) and 'u' is present in the answer.
A single letter 'p' remains which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for look up that I've seen before include "Search in dictionary or go to visit" , "Search for as in dictionary (4,2)" , "Search for information about, or elevate gaze" , "Show signs of improving" , "Check (reference); visit (friend)" .)