Meaning: Able to withstand attack. Synonyms: unassailable; unattackable; impregnable; inviolable; secure; strong. Context examples: an impregnable fortress / fortifications that made the frontier inviolable. Similar: invulnerable (immune to attack; impregnable)
Definition - What does Magnetic Disk mean? A magnetic disk is a storage device that uses a magnetization process to write, rewrite and access data. It is covered with a magnetic coating and stores data in the form of tracks, spots and sectors. Hard disks, zip disks and floppy disks are common examples of magnetic disks.
Magnetic storage is commonly used on the hard disc drives found on most computers. Information is stored using positive and negative magnetic charges to correspond with the 1s and 0s noted above. Optical discs like CDs and DVDs store information as binary code that can be read by an optical sensor in a disc drive.