Onomatopoeia:
A figure of speech in which natural sounds are imitated in the sounds of words

Example:
"Myriads of rivulets hurrying through the lawn,

The moan of doves in immemorial elms,

And murmuring of innumerable bees."

- The Princess, (Part vii) by Alfred Lord Tennyson

Explanation:

This has onomatopoeia in the "moan" of the doves and the "murmuring" of the bees. Tennyson does this to appeal to the readers sense of auditory imagery. This imagery creates an impression and abstraction to the reader, allowing them to further understand and enjoy the novel. Onomatopoeia allows the reader to further understand what they are reading, and keeps them interested and allows their imagination to flow.