Meaning to join doctor, if time (5)
I believe the answer is:
drift
'meaning' is the definition.
(drift is a kind of meaning)
'join doctor if time' is the wordplay.
'join' means one lot of letters go next to another.
'doctor' becomes 'Dr' (abbreviation).
'time' becomes 't' (abbreviation).
'dr'+'if' is 'drif'.
'drif'+'t'='DRIFT'
'to' is the link.
(Other definitions for drift that I've seen before include "Move with the current" , "Meander aimlessly" , "Import" , "Trend; meaning" , "Move with wind and tide" .)