Pronunciation: (ir"i-dOO'su-bul, -dyOO'-),[key] —adj. 1. not reducible; incapable of being reduced or of being diminished or simplified further: the irreducible minimum. 2. incapable of being brought into a different condition or form.
3. Math. a. of or pertaining to a polynomial that cannot be factored.
b. of or pertaining to a group that cannot be written as the direct product of two of its subgroups.