It's difficult to comprehend what scholars who bandy these terms around are talking about without an advanced degree in Literature, or at least a program, so here as a public service I present a little glossary to help you through those didactic and abstruse novel or poetry discussions. This device lends a kind of internal rhyme scheme to a poem that relieves the poet of the burden of finding words that mean exactly the right thing. A metrical foot composed of three syllables, of which only the second is accented. Or a frog with exceptionally long arms. A fascinating collection of myths, fables, fourth-hand accounts, and parables that has been mistranslated, revised, edited with a large scythe, reordered, expurgated, enlarged, abridged, and generally scrambled so many times over the last two thousand years that no one knows if any of the original text can be found embedded within it.
People routinely kill each other over the precise meaning of small parts of it.
Implied meaning, as assigned by the reader. This allows an author to be regularly and reliably misinterpreted by pedants looking to make their careers. I argue that Cleanth Brooks was dropped on the head repeatedly as an infant and right on through to adolescence, and therefore should be forgiven. Only with five feet per line. Any humorous works written by someone funnier than oneself.