Poem that begins "Once upon a midnight dreary," with "The" (5)
I believe the answer is:
raven
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">poem that begins once upon a midnight dreary with the</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for raven that I've seen before include "Crow-like bird" , "Bird in 1's poem" , "pig" , "flesh-eating bird" , "Flighty type" .)