Final answer:
A kenning is not a double metaphor; it is a poetic device that combines two words to indirectly refer to something else, often using metaphorical language.
Step-by-step explanation:
The statement that a kenning is a double metaphor is false. A kenning is a stylistic device found in Old Norse and Old English poetry.
It is a kind of circumlocution, in metaphoric language, where two words are combined in order to create an indirect reference to something else. For example, the term 'whale-road' is a kenning for the sea. While the kenning often involves metaphorical language, it is not correct to call it a double metaphor.