Very harsh wine downed by doctor with cold (7)
I believe the answer is:
drastic
'very harsh wine downed by doctor with cold' is the definition.
I can't tell whether this defines the answer.
'downed by doctor with cold' is the wordplay.
'downed' becomes 'asti' (I am not sure about this - if you are sure you should believe this answer much more).
'by' means one lot of letters go next to another.
'doctor' becomes 'dr' (abbreviation).
'with' says to put letters next to each other.
'cold' becomes 'c' (eg on taps).
'asti' put after 'dr' is 'drasti'.
'drasti'+'c'='DRASTIC'
Can you help me to learn more?
(Other definitions for drastic that I've seen before include "Severe - powerful" , "Extremely severe" , "Draconian" , "Very severe or serious" , "'Severe, extreme (7)'" .)