Saint telephones for violins? (7)
I believe the answer is:
strings
'for violins?' is the definition.
(violin is a kind of string)
'saint telephones' is the wordplay.
'saint' becomes 'st' (abbreviation).
'telephones' becomes 'rings' ('ring' can be a synonym of 'telephone').
'st'+'rings'='STRINGS'
(Other definitions for strings that I've seen before include "Lengths of wire etc on a musical instrument" , "Orchestral section" , "Just; trade exhibition" , "Undesirable conditions" , "Bowed instruments in the orchestra" .)