A more famous text describing these  distinguishes them from heiti, or synonyms.
The major work that describes the categories of these concepts distinguishes between those of them  which originate from incidental characteristics, and the sann variety, which originate from essences.  These concepts are divided into the simple, tvikent, or "double," and rekit, or "extended," variants in a text partial y concerned with these concepts titled the Hattatal. A more famous text describing these  distinguishes them from heiti, or synonyms. That work is framed as a conversation between Aegir, who  asks about the origins of these concepts and their classification, and Bragi, who explains their origin and  proceeds to list many examples of these concepts, such as those relating to fire, gold, and Heimdal .  Classified in a chapter of the Prose Edda cal ed the Skaldskaparmal and including examples such as  "al -father" for Odin, for 10 points, identify these devices of skaldic poetry, a kind of circumlocutory  reference.
The major work that describes the categories of these concepts distinguishes between those of them  which originate from incidental characteristics, and the sann variety, which originate from essences.  
kennings