poetic licence 
noun [mass noun]
The freedom to depart from the facts of a matter or from the conventional rules of language when speaking or writing in order to create an effect: he used a little poetic licence to embroider a good tale...
- No one is going to be able to get that document so in the end we're having to deal with some indisputable facts and some poetic licence.
- True poetry, however, is never entirely severed from the speaking voice; a certain latitude, however, sometimes called poetic licence, allows the poet to take liberties with language.
- There is a circular logic in the premise here and the anthropomorphy that renders objects sentient still niggles, despite allowance for poetic licence.