The word 'slag' is originally from German 'slagen'

'Slag' is a word borrowed from German 'slagen'. The word entered the English language some time around 1971.

slag [verb] [1971]

To criticize harshly

See 'slag' on the Loan Words Map

See more loan words from German.

Etymology: Probably from 'slag'

See more loan words from 1970s.