in anatomy, the womb, or that part of the female of any kind, wherein the fetus is conceived and nourished till the time of its delivery. See Anatomy, no 108.

Matrix is also applied to places proper for the generation of vegetables, minerals, and metals. Thus the earth is the matrix wherein seeds sprout; and marcasites are by many considered as the matrices of metals.

The matrix of ores is the earthy and stony substances in which these metallic matters are enveloped: these are very various, frequently spar, quartz, fluors, or horn-blend.