Industrious worker initially refused drink (4)
I believe the answer is:
beer
'drink' is the definition.
(beer is a kind of drink)
'industrious worker initially refused' is the wordplay.
'industrious worker' becomes 'bee' (a worker bee. I am not sure about the 'industrious' bit.).
'initially' indicates taking the first letters.
The first letter of 'refused' is 'r'.
'bee'+'r'='BEER'
Can you help me to learn more?
(Other definitions for beer that I've seen before include "Perhaps bitter" , "Stout, for example" , "See 4 down" , "Fermented alcoholic beverage" , "... this at pub?" .)