What is the matrix, or cavity, in which anything is shaped, and from which it takes its form; also, the body or mass containing the cavity; as, a sand mold; a jelly mold. Milton called?

mould — The matrix, or cavity, in which anything is shaped, and from which it takes its form; also, the body or mass containing the cavity; as, a sand mold; a jelly mold. Milton. (Webster's 1913.)

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