In edgar allan poe’s “the raven,” the speaker says, “much i marveled this ungainly fowl to hear discourse so plainly.” what does the speaker mean when he describes the raven as “this ungainly fowl”?

"fowl" means bird, and a raven is a type of bird. so, simply put, the author is just referring to the raven with a different term. "ungainly" means awkward or clumsy, so I assume the raven he's speaking of is moving about in a clumsy sort of way?

I'm not sure if that's the answer you wanted, if not let me know and I'll try to help as best I can.