Musical tea break about six (5)
I believe the answer is:
evita
'musical' is the definition.
(I've seen this before)
'tea break about six' is the wordplay.
'break' indicates anagramming the letters.
'about' is an insertion indicator.
'six' becomes 'vi' (roman numeral).
'tea' anagrammed gives 'eta'.
'eta' enclosing 'vi' is 'EVITA'.
(Other definitions for evita that I've seen before include "Famous musical" , "Well-known musical" , "Show" , "Musical based on Argentine leader" , "1996 musical film, starring Madonna" .)