Other forms: sacked, sacks, sacking
A sack is a big bag of rough cloth or heavy paper, the kind that holds things by weight: a sack of potatoes, a sack of cement, a sack of flour over a baker's shoulder. It has no handles, and it slumps when you set it down.
In British and Australian English the sack is also losing your job — he got the sack, they sacked half the department — and it is informal, so an official letter says dismissed instead. To sack a city is something else entirely: soldiers pulling a captured town apart, as in the sack of Rome. Hit the sack means go to bed. Sackcloth survives mainly in sackcloth and ashes, for making a show of being sorry. And in American football, to sack the quarterback is to bring him down behind the line.
1nounsackA large bag made of strong cloth or thick paper.
“He heaved a sack of coal onto his shoulder.”
2noundismissalDismissal from a job.
“Three of them got the sack after the audit.”
3verbdismissTo dismiss someone from a job.
“She was sacked for turning up late one time too many.”
4verbrobTo rob and destroy a captured town.
“The city was sacked and burned in a single night.”
5nounrobbingThe robbing and destruction of a captured town.
“The sack of the city lasted three days.”
Too few real examples of this word to estimate which sense is commonest.
sack is a bag.
Sack is one of the best-travelled words in English. Old English sacc came from Latin saccus, 'large bag', which came from Ancient Greek σάκκος, 'bag of coarse cloth', and Greek had taken it from a Semitic language — its relatives sit in Hebrew, Aramaic and Akkadian. The same bag turns up in Dutch zak, German Sack and Swedish säck.
Ancient Greek
σάκκος — bag of coarse cloth
Latin
saccus — large bag
Proto-Germanic
*sakkuz — sack
Proto-West Germanic
*sakku
Old English
sacc — sack, bag
Middle English
sak
English, today
sack
Built from
From Middle English sak, sek, sach, zech (“bag, sackcloth”), from Old English sacc (“sack, bag”) and sæċċ (“sackcloth, sacking”); both from Proto-West Germanic sakku, from late Proto-Germanic sakkuz (“sack”), borrowed from Latin saccus (“large bag”), from Ancient Greek σάκκος (“bag of coarse cloth”), from sem, possibly phn - or Hebrew. Cognate with Dutch zak, German Sack, Swedish säck, Danish sæk, Norwegian Bokmål and Norwegian Nynorsk sekk, Faroese and Icelandic sekkur, Hebrew שַׂק (“sack, sackcloth”), arc סַקָּא, syc ܣܩܐ, gez ሠቅ, akk 𒆭𒊓, egy sꜣgꜣ. a doublet of sac and saccus and saco and sakkos. Černý and Forbes suggest the word was originally Egyptian, a nominal derivative of sꜣq (“to gather or put together”) that also yielded cop ⲥⲟⲕ (“sackcloth”) and was borrowed into Greek perhaps by way of a Semitic intermediary. However, Vycichl and Hoch reject this idea, noting that such an originally Egyptian word would be expected to yield Hebrew סַק rather than שַׂק. Instead, they posit that the Coptic and Greek words are both borrowed from Semitic, with the Coptic word perhaps developing via egy sꜣgꜣ.
Etymology from Wiktionary, CC BY-SA