Then Ægir said, ‘In how many ways do you vary the diction in poetry, and how many types of poetry are there?’
Bragi replied, ‘All poetry belongs to one or another of two types.’
Ægir asked, ‘Which two?’
Bragi said, ‘We classify poetry according to diction and metre.’
‘What kind of diction is used in poetry?’
‘There are three categories.’
‘What are those?’
‘I’ll tell you. One, to name things by their ordinary names. Two, to substitute alternative names. Three, to use what are called kennings. To understand this third type of diction, suppose that in a poem I use the name Odin or Thor or Tyr, or some other name identifying one of the Æsir or the elves, but add to it a characteristic or attribute that properly belongs to another god or elf. Then it is this other personage that is referenced in the kenning and not the one actually named. For instance, I might say Tyr of victory or Tyr of the hanged man or Tyr of the cargo, and then in each case I am adding a piece of diction that relates to Odin. The phrase as a whole then refers to Odin, not to Tyr. We call that a “name with identifying attribute” [kent heiti]. An example is Tyr of the wagon, referring to Odin.’