Out of bed, father after cold drink (5)
I believe the answer is:
cuppa
'drink' is the definition.
(cuppa is a kind of drink)
'out of bed father after cold' is the wordplay.
'out of bed' becomes 'up' (synonyms).
'father' becomes 'pa' (pa can mean dad or father).
'after' means one lot of letters go next to another.
'cold' becomes 'C' (eg on taps).
'up'+'pa'='uppa'
'uppa' put after 'c' is 'CUPPA'.
(Other definitions for cuppa that I've seen before include "Refreshing brew" , "Drink of tea (colloq.)" , "Drink of tea (informal)" .)