Legend

Legends, like myths, were popular but unconfirmed stories.
According to the Tenth Doctor, there were representations of a horned Beast in the myths and legends of a million planets across the universe. (TV: The Satan Pit)
The Menoptera had legends of the First Doctor and the TARDIS. (PROSE: The Lair of Zarbi Supremo)
The Martians held an ancient legend about a "certain Panda deity who visited them in a scarlet chariot that came from the stars...". As such, the Martians were panda-phobic. (PROSE: Enter Wildthyme)
Clive Finch told Rose Tyler that the Doctor was "a legend woven throughout history". (TV: Rose)
Jack Harkness had heard legends of Gallifrey that made the planet sound perfect. (TV: The Sound of Drums) He had also believed the Last Great Time War to be a legend. (TV: The Parting of the Ways) The Sontarans, who were forbidden from taking part in the conflict, had heard of legends stating that the Doctor led the battle. (TV: The Sontaran Stratagem)
By 5,000,000,023, legends told that the Face of Boe had lived for millions, even billions of years, had watched the universe grow old, and would pass a great, final secret to a lonely traveller just before his death. Indeed, in 5,000,000,053, the Face of Boe told the Tenth Doctor, who believed himself to be the last of the Time Lords, that he was not alone before dying. (TV: New Earth, Gridlock)
Before meeting them in his tenth incarnation, the Doctor believed the Cult of Skaro to be a legend. (TV: Doomsday)
In 2009, the Shadow Architect believed that the Time Lords were the stuff of legend. (TV: The Stolen Earth)
By the year 100,000,000,000,000, shortly before the end of the universe, the Tenth Doctor, who identified as the last of the Time Lords, and the TARDIS were not recognised by the distant descendants of Earth humans who resided on Malcassairo. He said that he thought the end of the universe was a "bit humbling" after learning there were no legends and "not even a myth" about him. (TV: Utopia)
The Dalek Asylum was considered a legend, even by the Eleventh Doctor, though he doubted the planet's existence until he was brought to it. (TV: Asylum of the Daleks)
In his crusades against the Daleks, Rusty had become a legend across the galaxy, albeit one that some people had difficulty believing in, given the unlikeliness of a "good Dalek". (TV: Twice Upon a Time)
The Twelfth Doctor believed Robin Hood to be a legend, maintaining this belief after he met the man before the Sheriff of Nottingham made the Doctor see the truth. For his part, Robin was content to become a legend, believing that he could leave a longer lasting legacy in that manner. (TV: Robot of Sherwood)
According to one legend, Xaos was the oldest planet in its galaxy, and the origin of all life. (COMIC: The Warrior's Story)