Calls loudly and turns to buy drinks? (6)
I believe the answer is:
shouts
This clue is a double definition.
'calls loudly' is the first definition.
'turns to buy drinks?' is the second definition.
(a shout is someone's turn to buy drinks)
'and' acts as a link.
(Other definitions for shouts that I've seen before include "Sudden, loud cries" , "Utters a sudden loud cry" , "Bawls" .)