Doctor wears tie, so to speak (2,2,4)
I believe the answer is:
as it were
'so to speak' is the definition.
(synonyms)
'doctor wears tie' is the wordplay.
'doctor' is an anagram indicator.
'wears'+'tie'='wearstie'
'wearstie' anagrammed gives 'AS IT WERE'.
(Other definitions for as it were that I've seen before include "Just like if really so" , "In sort of" , "So to speak" , "Seemingly" , "you might say" .)