Toclafane
Template:Pre-broadcast spoiler
The Toclafane were fairy tale monsters from Gallifrey, their name, like the Bogeymen on Earth, just made up.
In 2008, the Master claimed to have contacted the Toclafane (in reality a race of robotic beings) and, using a paradox machine linked to the Doctor's TARDIS, allowed the enture race to pour through to decimate the Human population and create a Time Lord Empire. (DW: The Sound of Drums / Last of the Time Lords)
The "Toclafane" may not be their real names, but maybe the name was used and based on the Gallifreyan legend.
Russell T Davies is known to be quite a fan of anagrams, and the anagram of toclafane is 'a conflate'. The toclafane are either the following:
1: A mix of dalek DNA and the DNA of the last surviving humans in the universe in the episode Utopia.
2: A mix of dalek DNA and the doctor's DNA.