Ballads of bravery (1877) part of Arthurian mythology
Definitions of myth to some extent vary by scholar. Finnish folklorist Lauri Honko offers a widely cited definition:
Myth, a story of the gods, a religious account of the beginning of the world, the creation, fundamental events, the exemplary deeds of the gods as a result of which the world, nature and culture were created together with all parts thereof and given their order, which still obtains. A myth expresses and confirms society's religious values and norms, it provides a pattern of behavior to be imitated, testifies to the efficacy of ritual with its practical ends and establishes the sanctity of cult.
Scholars in other fields use the term myth in varied ways. In a broad sense, the word can refer to any traditional story, popular misconception or imaginary entity.
However, while myth and other folklore genres may overlap, myth is often thought to differ from genres such as legend and folktale in that neither are considered to be sacred narratives. Some kinds of folktales, such as fairy stories, are not considered true by anyone, and may be seen as distinct from myths for this reason. Main characters in myths are usually gods, demigods or supernatural humans, while legends generally feature humans as their main characters. However, many exceptions or combinations exist, as in the Iliad, Odyssey and Aeneid. Moreover, as stories spread between cultures or as faiths change, myths can come to be considered folktales, their divine characters recast as either as humans or demihumans such as giants, elves and faeries. Conversely, historical and literary material may acquire mythological qualities over time. For example, the Matter of Britain (the legendary history of Great Britain, especially those focused on King Arthur and the knights of the Round Table) and the Matter of France, seem distantly to originate in historical events of the fifth and eighth-centuries respectively, and became mythologised over the following centuries.
In colloquial use, the word myth can also be used of a collectively held belief that has no basis in fact, or any false story. This usage, which is often pejorative, arose from labeling the religious myths and beliefs of other cultures as incorrect, but it has spread to cover non-religious beliefs as well. However, as commonly used by folklorists and academics in other relevant fields, such as anthropology, the term myth has no implication whether the narrative may be understood as true or otherwise.
In present use, mythology usually refers to the collected myths of a group of people, but may also mean the study of such myths. For example, Greek mythology, Roman mythology and Hittite mythology all describe the body of myths retold among those cultures. Folklorist Alan Dundes defines myth as a sacred narrative that explains how the world and humanity evolved into their present form. Dundes classified a sacred narrative as "a story that serves to define the fundamental worldview of a culture by explaining aspects of the natural world and delineating the psychological and social practices and ideals of a society". Anthropologist Bruce Lincoln defines myth as "ideology in narrative form."
The compilation or description of myths is sometimes known as mythography, a term which can also be used of a scholarly anthology of myths (or, confusingly, of the study of myths generally). Key mythographers in the Classical tradition include Ovid (43 BCE–17/18 CE), whose tellings of myths have been profoundingly influential; Fabius Planciades Fulgentius, a Latin writer of the late fifth to early sixth centuries, whose Mythologies (Latin: Mitologiarum libri III) gathered and gave moralistic interpretations of a wide range of myths; the anonymous medieval Vatican Mythographers, who developed anthologies of Classical myths that remained influential to the end of the Middle Ages; and the Renaissance scholar Natalis Comes, whose ten-book Mythologiae became a standard source for classical mythology in later Renaissance Europe. Other prominent mythographies include the thirteenth-century Prose Edda attributed to the Icelander Snorri Sturluson, which is the main surviving survey of Norse Mythology from the Middle Ages.
Because myth is sometimes used in a pejorative sense, some scholars have opted to use the term mythos instead. However, mythos now more commonly refers to its Aristotelian sense as a "plot point" or to a body of interconnected myths or stories, especially those belonging to a particular religious or cultural tradition. It is sometimes used specifically for modern, fictional mythologies, such as the world building of H.P. Lovecraft.
"Conscious generation" of mythology was termed mythopoeia by, amongst others, J.R.R. Tolkien. It was notoriously also suggested, separately, by Nazi ideologist Alfred Rosenberg.