Drink and drive in the morning (4)
I believe the answer is:
dram
'drink' is the definition.
(thesaurus)
'drive in the morning' is the wordplay.
'drive' becomes 'dr' (I've seen this in other clues).
'in the morning' becomes 'am'.
'dr'+'am'='DRAM'
'and' is the link.
(Other definitions for dram that I've seen before include "Measure of Scotch" , "Small drink of whisky" , "slug" , "Wee drop of whisky?" , "little weight" .)