it is aliterary form simply defined as a patterned expressions of ideas or imaginative terms usually containing rhymes and meters?

Poetry

Explanation:

In literature, poetry is defined as the written expression of thoughts and ideas that possesses a rhythmic quality. It is a form of free expression that allows an author - poet - to describe a situation, thought, or narrate a story in a dramatic and a very emotional, sometimes romantic, manner.

There are three main types of poetry: dramatic, lyrical, and narrative. A poem differs from a story due to the presence of rhymes and meters which make this literary device so unique.