swage v.

1650s, "a lurching or swaying, an unequal motion," from swag (v.). Meaning "ornamental festoon" (1794) is said to be probably a separate development from the verb (but compare swage).

The decorative arts sense of "informal cluster (of flowers, etc.)" is by 1794. The colloquial sense of "promotional material" (from recording companies, etc.) was in use by 2001, perhaps as an extension of this sense. Swag also was English criminal's slang for "quantity of stolen property, loot" from c. 1839. This might be related to earlier senses of "round bag" (c. 1300) and "big, blustering fellow" (1580s), which may represent separate borrowings from the Scandinavian source. "The primary meaning was 'a bulging bag'" [Klein]. Swag lamp is attested from 1966.

"one who shapes by means of a swage," 1881, agent noun from swage (v.). In Middle English it was the name of a tool used to make decorative grooves or borders (early 15c.).