Musek (m)
(with) definite article: Musekǎtoriginal: мусек(ът)
internal canal of a tube; conical (tapered), or cylindrical
Internal canal of the chanter [only?]; The bore?; Term not encountered in other sources (Not even in volume 9 of the dictionary of the Институтът за български език „Професор Любомир Андрейчин“ [Institute for Bulgarian language "Prof. Ljubomir Andrejčin"]).
Le Gonidec, Marie-Barbara: La cornemuse bulgare. In: Pastel 30 (Toulouse, 1996), p.26.