matrix (n.) Look up matrix at Dictionary.com
late 14c., "uterus, womb," from Old French matrice "womb, uterus," from Latin matrix (genitive matricis) "pregnant animal," in Late Latin "womb," also "source, origin," from mater (genitive matris) "mother" (see mother (n.1)). Sense of "place or medium where something is developed" is first recorded 1550s; sense of "embedding or enclosing mass" first recorded 1640s. Logical sense of "array of possible combinations of truth-values" is attested from 1914. As a verb from 1951.