Being consistent with Romanticism, I don't think that there is a specific and dogmatic definition of poetry. Wordsworth and the other Romantic thinkers offer a basic template of what poetry should consist of or how it should originate, and from there, the definition begins:
[Poetry should reflect] incidents and situations from common life...[D]escribe [those incidents] […] in a selection of language really used by men.
The basic idea is here that poetry should reflect "the spontaneous overflow of emotions." With this, the basic Romantic definition of poetry takes form. It enables the poet to focus on subjective and personal experiences as well as connecting with the natural setting and the narratives that can be externalized into a universal setting. Due to its highly subjective and personal nature, the definition of poetry is not a binding one or one that excludes because the nature of Romantic inquiry is one that does not seek to exclude as much as it seeks to include, so long as poetic expression follows the basic tenet of being subjective and individualized and seeks to bring the subjective into the realm of the universal through connection between the poet and the audience.