A Thneed is a highly versatile object knitted from the foliage of a Truffula Tree. According to the Once-ler, it is "A-fine-something-that-all-people need." It costs $3.98 (approximately $29.30 adjusted for inflation) according to The Lorax Book and The Lorax. It's name is a letter off from "The Need', to show that when a trendy item comes along, it becomes the need of people around the world, causing ever largening greed like electronic devices and board games, to name a few.