Physician flipping cross about cold temperature (6)
I believe the answer is:
doctor
'physician' is the definition.
(synonyms)
'flipping cross about cold temperature' is the wordplay.
'flipping' shows that the letters should be reversed in order.
'cross' becomes 'rood' (term for a crucifix).
'about' indicates putting letters inside.
'cold' becomes 'c' (eg on taps).
'temperature' becomes 't' (abbreviation).
'rood' reversed gives 'door'.
'c'+'t'='ct'
'door' going around 'ct' is 'DOCTOR'.
(Other definitions for doctor that I've seen before include "One treats the ill" , "Adulterate; medic" , "Eg, surgeon" , "Who, for example" , "bones" .)