Flower of Remembrance
From Tardis Wiki, the free Doctor Who reference
The Flower of Remembrance of the Lost Dead (PROSE: The Infinity Doctors) was a six-petaled golden yellow flower native to the Time Lord homeworld of Gallifrey.
In Gallifreyan culture, it was an omen of death. (PROSE: The Ancestor Cell) They were either held or grown in the Citadel. (PROSE: The Infinity Doctors) As a child, the Doctor saw the flower at many funerals. (PROSE: Dead Time)
Faction Paradox turned the TARDIS' exterior into a Flower of Remembrance during their invasion of the planet, and when Greyjan the Sane returned, the flowers fell from the skies above the Panopticon. (PROSE: The Ancestor Cell)