What is mortar or the like, laid between the joists under the boards of a floor, or within a partition, to deaden sound; -- in the United States usually called deafening called?

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Accepted Answer

pugging — (Arch.) Mortar or the like, laid between the joists under the boards of a floor, or within a partition, to deaden sound; -- in the United States usually called deafening. (Webster's 1913.)

What is mortar or the like, laid between the joists under the boards of a floor, or within a partition, to deaden sound; -- in the United States usually called deafening called?

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