Definition:
“A quotation set at the beginning of a literary work or one of its divisions to suggest its theme.”
“Epigraph.” Merriam-Webster.com Dictionary, Merriam-Webster,
https://www.merriam-webster.com/dictionary/epigraph. Accessed 31 Aug. 2022.
Informal
An epigraph is a quote placed at the beginning of a book or one of its chapters. It is most often used in order to convey the themes of the book or chapter it precedes.
Example: “Did I request thee, Maker, from my clay / To mould me man?” - John Milton, Paradise Lost
[This quote is placed before the first chapter of the novel Frankenstein by Mary Shelley.]
Etymology:
“Borrowed from Greek epigraphḗ "act of inscribing, inscription," noun of action from epigráphein "to mark the surface of, graze, scratch a mark on, inscribe."
“Epigraph.” Merriam-Webster.com Dictionary, Merriam-Webster,
https://www.merriam-webster.com/dictionary/epigraph. Accessed 31 Aug. 2022.
Purpose:
The main purpose of an epigraph is to convey the themes of the book or chapter it precedes. Authors commonly pick epigraphs which thematically relate to the topic of their literary text, giving the reader a preview to what will be explored throughout the book or chapter. An epigraph can also act as a way to set the tone for a text. Before a comedy, an author might put a quote that is meant to be funny to convey to the reader the tone of the work as a whole. Epigraphs are to be avoided when an author doesn’t want to give the reader a glimpse into what a text is about, instead choosing to let the reader discover that on their own. There are a few ways in which an epigraph can be misused. One way is when an author includes an epigraph that doesn’t match the tone of the text (although this can be done for purposeful dissonance). Another way is when a quotation is included that doesn’t really have any relevance to the text itself, leaving the epigraph as just a group of lines that take up space on the page.