Triangular Russian instrument (9)

I believe the answer is:

balalaika

(Other definitions for balalaika that I've seen before include "Three-stringed, triangularbodied Russian instrument" , "Foreign instrument" , "Instrument with three strings and a triangular body" , "Three-stringed instrument used to play Russian folk music" , "Stringed instrument used for Russian folk music" .)

I've seen this clue in The Guardian.

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