Amorphophallus konjac, commonly known as konjac, konnyaku, elephant yam, or devil’s tongue, is a perennial plant of the family Araceae. The name "konjac" comes from the Japanese konnyaku (蒟蒻), the name of a traditional food prepared from its tuber. It is native to warm subtropical to tropical regions of East and Southeast Asia, particularly China, Japan, and Indonesia where its starchy underground corm has been cultivated for over a thousand years.

Historically, konjac was valued in Chinese traditional medicine as a detoxifying, expectorant, and digestive aid. In Japan, it became an essential ingredient of shojin ryori (Buddhist vegetarian temple cuisine) in the form of konnyaku blocks and shirataki noodles, prized for their texture and ability to absorb flavors. In modern times, konjac has become popular worldwide as a dietary fiber source, most notably for its high content of glucomannan, used as a thickener, gelling agent, and dietary supplement for weight management, cholesterol reduction, and blood sugar regulation. The corm itself is generally not consumed raw due to the presence of calcium oxalate crystals, which cause irritation if improperly processed. Proper boiling, limewater treatment, and gelation make it safe and edible.