invariant section

/IH0 N V EH1 R IY0 AH0 N T S EH0 K SH AH0 N/
noun
  1. 1

    (programming) A property that does not change through a program's execution.

  2. 2

    (mathematics) A section that will not vary through changing state.

  3. 3

    (law) Something that must not be removed or modified during redistribution.