1slate 
/ˈsleɪt/ noun
plural slates /ˈsleɪt/ noun 1 [noncount] : a type of hard rock that splits easily into thin layers
▪ Some school blackboards are made of slate. 2 [count] : a small sheet of slate in a wooden frame that was used in schools in the past for writing on with chalk — see also blank slate 3 [count] : a piece of slate that is used with others to cover a roof or wall
▪ roofing slates ▪ The house has a slate roof. 4 [count] US : a list of people who are trying to win an election
▪ The party has fielded an impressive slate of candidates this year.
▪ Some school blackboards are made of slate.
▪ roofing slates ▪ The house has a slate roof.
▪ The party has fielded an impressive slate of candidates this year.
clean slate — see 1clean
wipe the slate clean — see 1wipe
