Violinist's need (3)
'violinist's need' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for rosin that I've seen before include "Violin bow treatment" , "Wax for violin bow etc." , "What gives bite to strings" , "No sir; it is rubbed on violin bows" , "Varnish etc. from turpentine" .)
'violinist's need' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for bow that I've seen before include "Stoop" , "Loose knot" , "Bend in obeisance" , "District in East London" , "Make reverence" .)