The American Heritage Dictionary defines this as:
a) A dramatic or literary form of discourse in which a character talks to himself or herself or reveals his or her thoughts without addressing a listener.
B) A specific speech or piece of writing in this form of discourse.
There are many soliloquies on this site, including the most famous of them all: “To be or not to be,” from Shakespeare’s Hamlet.
To help improve the meaning of these lyrics, visit "Glossary of Poetic Terms" by Genius Educators (Ft. Poetry Genius Editors & Rap Genius Editors) and leave a comment on the lyrics box