- Any mail or letters that are not welcome or solicited and typically sent in bulk; especially mail of a commercial nature such as advertising circulars and form letters.
2013 May 25, “No hiding place”, in The Economist, volume 407, number 8837, page 74:
- In America alone, people spent $170 billion on “direct marketing”—junk mail of both the physical and electronic varieties—last year. Yet of those who received unsolicited adverts through the post, only 3% bought anything as a result.
mail or letters that are not welcome or solicited