Definition of "Slate" :

noun: (formerly) a writing tablet made of slate

noun: a list of candidates nominated by a political party to run for election to public offices

noun: a fine-grained metamorphic rock that can be split into thin layers

noun: thin layers of rock used for roofing

verb: designate or schedule

"He slated his talk for 9 AM."

verb: cover with slate

"Slate the roof."

verb: enter on a list or slate for an election

"He was slated for borough president."