A sarcastic urban dictionary entry defines the chorus as “The part of a song you actually remember,” and there’s more to that joke than just the humor value. In most popular music, the chorus can easily be identified because it is uses the same lyrics each time we hear it, and it frequently uses the title of the song. Most definitions of chorus mention the repetition of text or appearance of the song title; for example, in his massive two-volume study of the Beatles’ music, Walter Everett says that “The chorus, which gets its name from a usual thickening of texture from the addition of backing vocals, is always a discrete section that nearly always prolongs the tonic and carries an unvaried poetic text” (Everett 1999, p. 19). The repetition of lyrics in the chorus sets off that section from the verse, which usually has different lyrics each time it is heard. “the verse is to be understood as a unit that prolongs the tonic….The musical structure of the verse nearly always recurs at least once with a different set of lyrics” (Everett 1999, p. 15). Because we hear the chorus sung the same way over and over, it becomes the most memorable part of the song
But in Iron Maiden’s “Remember Tomorrow,” this definition doesn’t work. There is a part of the song with repeating text: the stanza that begins at 0:21 is repeated almost exactly at 3:55. But it’s not that memorable or something you’d normally sing along with, and the same music occurs at 1:28 with different lyrics. That would mean that this song has a chorus and a single verse, followed by a long bridge, then a second chorus, which would be a really odd song form. It makes a lot more sense to view each of the sections with lyrics (which all have the same music) as verses, with the first and last verse having the same lyrics. Then does this song even have a chorus?