County north of the Firth of Forth (4)

I believe the answer is:

fife

(Other definitions for fife that I've seen before include "Mil. flute" , "Old Scottish county - musical instrument" , "St Andrews area" , "Shrill flute; Scots region" , "Small flute - ancient kingdom of central Scotland" .)

I've seen this clue in The New York Times.

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