Absinthe is defined in medical terms as a highly alcoholic (45-74% alcohol by volume) distilled beverage which has historically been produced using wormwood (Artemisia absinthium), anise, and florence fennel. It was traditionally bottled at a high proof and then diluted with water prior to consumption.

Absinthe has a distinctive green color, although some varieties are colorless. It is known for its strong, unique licorice flavor due to the presence of anise, as well as its potentially psychoactive effects. The active chemical in wormwood, thujone, was believed to cause hallucinations and other mental disturbances, giving absinthe a reputation as a dangerous and addictive substance.

However, modern research has shown that the levels of thujone in historical absinthes were not high enough to produce such effects, and the bans on absinthe in many countries during the early 20th century were largely based on misinformation and moral panic. Today, absinthe is once again legal in many parts of the world, although it is subject to stricter regulations than other alcoholic beverages.