This is the kind of big, spooky, complicated image that Poe just loves. It sounds spiffy and poetic, and it also manages to ball a bunch of mysterious images into one phrase. The phrase has three words, and also three parts:
- The Night. Darkness and night are both major symbols in this poem. They both represent the mysterious, maybe dangerous and scary power of nature. In addition, they just make for a cool atmosphere for a poem – it definitely couldn't take place on a sunny afternoon.
- Plutonian. This is an allusion to the Roman god of the underworld. The adjective "Plutonian" is meant to make us think of all the scary things that one associates with the underworld: darkness, death, the afterlife etc.
- Shore is a little more mysterious. It may be a metaphor that helps us to see the night as a vast ocean, washing up against the edge of this chamber.In a way, then, all these words help emphasize the ideas of darkness and night. Not just a dreary night, but also a vast ocean of hellish darkness. Very much Poe's style.
- Line 47: This is the first time this phrase gets used. It associates the raven with the night, and since the speaker asks for the bird's "lordly name," we almost feel like he could be the king of the night.
- Line 98: The phrase used here gets echoed later in the poem. Poe does this a lot, with all kinds of phrases. Where before the idea of the night was kind of intriguing to the speaker, now he just wants the bird gone. Since the narrator is all worked up now, we get a much stronger sense of how scary and threatening this Plutonian night really is.