Unclear etymology. Initially:a giant.
Contrary to an idea spread by romanticism, the troll is not a more or less prankish dwarf or elf. He is a frightful evil giant (the Church will equate him with the devil:"May the devil take you" will say troll hafi thik, "May the troll possess you") and sometimes monstrous, in a mythology where monsters are rare. It seems that, like the alves, the trolls have been credited with power over our mental faculties:terms for our sorcery, magic, etc. are all troll-based compounds (thus trolldom magic; trollkarl:magician; trollviser:magic songs). From the time of the converting kings of Norway (Ôlâfr Tryggvason, then Olâfr Haraldsson the Saint, end of the 10th century-beginning of the 11th century), it was against the trolls that the activity of Christian proselytes was first directed. . A solid tradition will be established around this theme:it survives in ballads, songs and popular tales, particularly numerous in the North. It is also by virtue of the constant effort of devaluation carried out by the Church that the size of these primitive giants has continued to shrink. But they will not be taken for dwarfs or harmless creatures. Sometimes trolls condescend to marry off their - usually beautiful - daughters to gods!
A seductive theory would like to make them the dead dissatisfied with their fate, like the Icelandic draugr. This is not excluded:in the present state of our knowledge and our sources, it is obvious that all the categories of Nordic supernatural creatures overlap and that, to remain in the semantic area where we are here, the notion of "giant" ended up intersecting with all sorts of other mythical realities.
It is Norway that has kept the most vivid memory of the trolls they inhabit popular tales that have been the subject of numerous illustrated editions. Human-sized, they are usually stupid and ugly - with a "long as a poker" nose and a bushy tail that sticks out of their pants; if they show themselves to be evil, they should be circumvented, an easy thing because of their stupidity. They can in some cases be helpful.
Their extreme ugliness, even their monstrousness, explains why they survive in toponymy:the fantastic formations of the Norwegian soil, for example, justify a number of names where the word "troll" enters:thus Trollahals, Trollaskôgr or Trollatunga (respectively, "throat", "forest" or "troll tongue"). The great Norwegian writer Ibsen, in Peer Gynt, clearly saw both the ambiguity and the subtlety of the notion of troll.