Anion
From Tardis Wiki, the free Doctor Who reference
Anions were negatively-charged atoms. They affected osmosis in plants that lived by the sea. They also "steadily sap[ped] energy". Trisilicate was made up of anions. Sekhmet's tomb was made of trisilicate so that the anions would weaken her the longer she stayed inside. (AUDIO: The Bride of Peladon [+]Loading...["The Bride of Peladon (audio story)"])
