Beverage for doctor at home with king (5)
I believe the answer is:
drink
'beverage' is the definition.
(I know that beverage can be written as drink)
'doctor at home with king' is the wordplay.
'doctor' becomes 'dr' (abbreviation).
'at home' becomes 'in' ('I'm in' can mean 'I'm at home').
'with' means one lot of letters go next to another.
'king' becomes 'K' (chess abbreviation).
'dr'+'in'+'k'='DRINK'
'for' is the link.
(Other definitions for drink that I've seen before include "Liquid refreshment" , "Booze" , "Demon beverage?" , "Possibly shake" , "Tipple" .)