Pronunciation: mā′triks, mat′riks; mā′tri-sēz, mat′ri-sēz
1. The formative portion of a nail.
2. The intercellular substance of a tissue.
3. A surrounding substance within which something is contained or embedded, the fatty tissue in which blood vessels or lymph nodes lie provides a matrix for these embedded structures.
4. A mold in which anything is cast or swaged; a counterdie; an instrument, plastic material, or metal strip specially shaped for holding and shaping the material used to fill a tooth cavity.
5. A rectangular array of numbers or symbol quantities that simplify the execution of linear operations of tedious complexity, the Ito method; the theory of matrices is widely used in solving simultaneous equations and in population genetics.
6. The support or stationary phase in chromatography or zone electrophoresis.
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