Family name origins & meanings
- English and Dutch : nickname for an idle person, from Middle Dutch slac, Middle English slack, ‘lazy’, ‘careless’.
- English : topographic name from northern Middle English slack ‘shallow valley’ (Old Norse slakki), or a habitational name from one of the places named with this word, for example near Stainland and near Hebden Bridge in West Yorkshire.
- Scottish (Dumfriesshire) : habitational name, maybe from Slake or Slack in Roberton, Roxburghshire (now part of Borders region).
- It may also be an Americanized spelling of Slovenian Slak, a nickname from slak ‘bindweed’.