slate

n. fine grained rock that is easily split into thin layers; writing surface made of slate; shingle made of slate or a similar material; list of candidates; greyish blue color

v. cover with slate (of a roof, etc.); nominate a candidate for office; propose or list for candidacy; schedule, plan; harshly criticize, denounce, abuse

Slate is a fine-grained, foliated, , metamorphic rock derived from an original shale-type sedimentary rock composed of clay or volcanic ash through low grade regional metamorphism. The result is a foliated rock in which the foliation may not correspond to the original sedimentary layering.
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Noun
1. (formerly) a writing tablet made of slate
(hypernym) tablet
2. thin layers of rock used for roofing
(synonym) slating
(hypernym) roofing material
3. a fine-grained metamorphic rock that can be split into thin layers
(hypernym) sedimentary rock
4. a list of candidates nominated by a political party to run for election to public offices
(synonym) ticket
(hypernym) list, listing
Verb
1. designate or schedule; "He slated his talk for 9 AM"; "She was slated to be his successor"
(hypernym) intend, destine, designate, specify
2. enter on a list or slate for an election; "He was slated for borough president"
(hypernym) cross-file, register
(derivation) ticket
3. cover with slate; "slate the roof"
(hypernym) roof
(derivation) slating

(v. t.)
To set a dog upon; to bait; to slat. See 2d Slat, 3.
  

(v. t.)
To register (as on a slate and subject to revision), for an appointment.
  

(v. t.)
To cover with slate, or with a substance resembling slate; as, to slate a roof; to slate a globe.
  

(v. t.)
Any rock or stone having a slaty structure.
  

(v. t.)
An artificial material, resembling slate, and used for the above purposes.
  

(v. t.)
An argillaceous rock which readily splits into thin plates; argillite; argillaceous schist.
  

(v. t.)
A thin, flat piece, for roofing or covering houses, etc.
  

(v. t.)
A thin plate of any material; a flake.
  

(v. t.)
A tablet for writing upon.
  

(v. t.)
A prepared piece of such stone.
  

(v. t.)
A list of candidates, prepared for nomination or for election; a list of candidates, or a programme of action, devised beforehand.
  

A fine-grained, foliated metamorphic rock that develops from shale and tends to break into thin, flat sheets.