Cyberarmour
Cyberarmour or Cyber armour was the distinctive metal armour which made up the body of the Cybermen. (PROSE: Illegal Alien, Plague of the Cybermen, TV: The Timeless Children)
In certain cases in which the cyber-conversion process was left incomplete, individuals such as Gustave Lytton, Lisa Hallett and Ashad were left with their organic bodies partially exposed beneath the Cyber armour. (TV: Attack of the Cybermen, Cyberwoman, The Haunting of Villa Diodati)
In Pete's World, Cybermen created by Cybus Industries on Earth were originally composed of Cyber armour suits, with the only organic component being the human brain. (TV: Rise of the Cybermen) Later, these Cybermen were forced to perform a quicker upgrade process which entailed the application of Cyber armour to human bodies. Lisa Hallett was subjected to this process partially during the Battle of Canary Wharf. (TV: Cyberwoman)
The armour of Cybermen was impervious to bullets. (TV: Rise of the Cybermen) However, they were susceptible to electromagnetic bombs, (TV: The Age of Steel) energy blasters and Dalek gunsticks. (TV: Doomsday) In addition, the Cybermen proved vulnerable to their own in-built weaponry, such as the wrist blasters. (TV: Death in Heaven, The Timeless Children)
By default, Cyber-drones were fitted with partial Cyber armour. (COMIC: The Power of the Cybermen)
The CyberMasters, Cyber-Warriors converted from dead Time Lords, were able to regenerate beneath the Cyber armour. (TV: The Timeless Children)
Mercy Hartigan referred to the surviving Cybus Cybermen as her "knights in shining armour, quite literally". (TV: The Next Doctor)