Junk mail is a term used to describe unwanted mail, such as unsolicited advertisements and solicitations. The two crossword solutions for the term 'junk mail' are SPAM (4 letters) and LITTERATURE (11 letters). SPAM is an electronic form of junk mail that is sent out in bulk via email or other digital messaging systems. LITTERATURE is a term used to describe printed materials, such as flyers, brochures, and catalogs, which are often sent out as junk mail.