Physical servers, with an implication that it's litrally just the hardware and no service level on top. Similar to when people talk about bare metal servers.
For many the detail of the hardware does not matter Eg. "Once the packet hits the tin it's no longer my problem". Also talking about a £50k pile of servers as just "tin that needs to be racked" could be a backhanded way of signalling confidence in the task, where others might be intimidated by the cost of the equipment they are dealing with.