English and Scottish: chiefly from Middle English blak(e) ‘black’ (Old English blæc, blaca), a nickname given from the earliest times to a swarthy or dark-haired man. However, Middle English blac also meant ‘pale, wan’, a reflex of Old English blāc ‘pale, white’ with a shortened vowel. Compare Blatch and Blick . With rare exceptions it is impossible to disambiguate these antithetical senses in Middle English surnames. The same difficulty arises with Blake and Block .

Scottish: in Gaelic-speaking areas this name was adopted as a translation of the epithet dubh ‘dark, black-(haired)’, or of various other names based on Gaelic dubh ‘black’, see Duff .

Americanized form (translation into English) of various European surnames directly or indirectly derived from the adjective meaning ‘black, dark’, for example German and Jewish Schwarz and Slavic surnames beginning with Čern-, Chern- (see Chern and Cherne ), Chorn-, Crn- or Czern-.