1. A bag made of any of a variety of materials, used for containing or carrying items: Rena asked the farmer if she could buy a sack of apples.
2. A specifically designed bag typically with shoulder straps used for carrying heavy items; such as, camping or hiking gear: Each scout had a hiker's sack to carry while they were going for a walk.

Sacks were originally made of coarse cloth similar to those that were used in making "gunnysacks". The word sack came from Hebrew sag, "sack", "sackcloth".

In the Bible, "sackcloth and ashes" refers to the wearing of rough sackcloth garments and sprinkling ashes on the heads by those who are showing that they are sorry for sins or wrong doing that they have done.

3. Etymology: from sachet which is French for "little bag"; specifically, "a small ornamented bag" for carrying perfumed powder or something of a similar nature."

1. To pack or to place something in a bag: Marven was hired one summer to sack grain at a farm.
2. To rob, to loot, or to pillage: The invaders sacked the village of anything of value.

The expression to sack, meaning "to loot", comes from the use of sacks by looters as a convenient means of carrying away their stolen goods.