harddisk

/HH AA1 R D IH0 S K/
noun
  1. 1

    One of a series of parallel magnetic recording disks in a drive unit, used for the recording and retrieval of digital information; used especially in personal computers.

  2. 2

    The unit itself, and all the disks within it.

Source: https://en.wiktionary.org/wiki/hard%20disk, https://en.wiktionary.org/wiki/harddisk