unbreakable

/AH0 N B R EY1 K AH0 B AH0 L/
noun
  1. 1

    Something that cannot be broken.

adjective
  1. 1

    Difficult to break and therefore able to withstand rough usage

  2. 2

    (of a horse) not able to be broken in

Source: https://en.wiktionary.org/wiki/unbreakable