Element

Elements were, according to the Eleventh Doctor, forged in the heart of stars million of years in the past. The explosion of these stars scattered the elements into space and formed new stars and planets. They continued to come together and burst apart to form "shoes and ships and sealing wax, and cabbages and kings" and eventually formed lifeforms like Merry Gejelh. (TV: The Rings of Akhaten)

Elements were organised into the periodic table. (TV: The Krotons, PROSE: Iris Wildthyme y Señor Cientocinco contra Los Monstruos del Fiesta)