Liverworts were named during the Middle Ages, when herbalists followed the theoretical approach known as the Doctrine of Signatures. The core philosophy of this perspective was that if a plant part resembled a part of the human body, it would be useful in treating ailments of that organ or part. The thallus of thalloid liverworts resembles a lobed liver. Therefore, in line with the philosophy presented by the doctrine, the plant was used to treat liver ailments. The word “liver” was combined with “wort,” which means herb, to form the name “liverwort.”

Mosses, liverworts, and hornworts—collectively known as bryophytes—are often found in moist environments. However, there are species that inhabit almost all environments, from hot, dry deserts to the coldest regions of Antarctica. They are most noticeable when they grow in a dense mass. They are generally small, compact plants that rarely grow to more than 8 inches (20 centimeters) tall. They have parts that appear leaflike, stemlike, and rootlike, and lack vascular tissue (xylem and phloem).