sack [OE] When it refers to a bag, sack is related to Dutch zak and German Sack, and goes back to Semitic, the family of languages that includes Hebrew and Arabic. The word passed through Greek and Latin into the language of the Continental Anglo-Saxons, who brought it with them to England, leaving us with the interesting question of what words were being used for an object that these cultures must have had before the borrowing, and why they felt the need to borrow it. Latin saccus is the source of the biological sac [M18th] and, via French, of sachet [M19th] and satchel [OE] both ‘a little sack’. The sack meaning ‘to plunder or pillage a town or city’ came in the mid 16th century from French, where the phrase was mettre à sac, ‘to put to the sack’. This may have originally referred to filling a sack with plunder, so the two words would ultimately be the same.

People in employment have been given the sack since the early 19th century, probably echoing a French phrase. Sacks were made of a coarse rough fabric woven from flax and hemp, called sackcloth. The Gospel of St Matthew describes the wearing of sackcloth and the sprinkling of ashes on your head as signs of repentance and mourning, and people experiencing these emotions can still be in sackcloth and ashes. See also rucksack.