Fabric hung in swags as a window dressing

A burglar carries a bag marked "swag" - common in children's illustrations

The term swag may refer to one of the following:

• A wreath or garland suspended from two points, also fabric hung from two points
• A subsidence in the ground
• Goods taken by a thief or burglar
• In Australia and NZ, a swag is the traditional roll of belongings carried by a traveller in the bush. See also swagman
• (especially Australia and NZ) a large amount of something
• The novel Swag, by Elmore Leonard

Also spelled "shwag" or "schwag"

• A slang term for promotional items, usually given away for free. Some people suggest that it is an acronym for shit (or stuff) we all get, but this is not supported by the fact it is very often spelled schwag or shwag; more likely derived from swag in the sense of stolen or scavenged loot as above.
• Other items not given to the public, but made by crews on certain teams, especially movie special effects teams.
• A form of low-quality, cheap cannabis that has many stems and seeds. Produces a lesser high than that of kind bud, or mid-grade, comerc, high grade, dank, etc.
• The Star Wars Artists' Guild.

As an abbreviation, SWAG stands for "scientific wild-assed guess" or "silly wild-assed guess".