thneed
A useless product which is advertised as being needed by everybody, but which in fact no one needs.
Do You Really, I Mean REALLY, Need a Thneed?
Where it comes from
Coined in 1972 by Theodor "Dr. Seuss" Geisel in the children's book The Lorax, as a rhyme for English need.
Adapted from the Wiktionary entry thneed (CC BY-SA 4.0).