Master has drink with singer (7)
I believe the answer is:
teacher
'master' is the definition.
(I've seen this before)
'drink with singer' is the wordplay.
'drink' becomes 'tea' (tea is a drink).
'with' means one lot of letters go next to another.
'singer' becomes 'cher' (Cher is a US musician).
'tea'+'cher'='TEACHER'
'has' acts as a link.
(Other definitions for teacher that I've seen before include "Pedagogue" , "The race (anag.)" , "School educator" , "Schoolmaster" , "The trainer" .)