Hide

A hide was the skin of an animal. As Ace once observed on Arden, the Shenn, at one point in their history, had used the "hides of various animals for disguise and protection". (PROSE: Shadowmind) The Seventh Doctor also claimed to know of a country where the citizens made mats from the hides of the Uncommon Green Bear, and then laid them on the pavement to prevent walking on the cracks. (PROSE: The Death of Art)

As colloquialism
Because humans were considered to have hides, a number of expressions arose, most of them to imply a metaphoric threat. For instance Captain Jack Hobson once issued the general threat that he'd "tear the hides off" anyone who had been tampering with the Moonbase's compression chamber. (TV: The Moonbase) Similarly, another base commander, General Cutler, once promised to "have [the] hides" of any of his men who failed a particular assignment he'd given them. (TV: The Tenth Planet) Sezon also used this expression to indicate his displeasure with he and others in his rebellion had become lax. (PROSE: Timelash)