Per Benjamin Dreyer:
"Perhaps you’ve run across the term “mondegreen”? I’ve long known it to mean a misheard lyric or bit of poetry, but its full meaning I learned only minutes ago — because I finally deigned to investigate. “Mondegreen” was coined in 1954 by writer Sylvia Wright to commemorate her having misapprehended the phrase “laid him on the green,” in this line from a Scottish ballad: “They have slain the Earl of Moray / An’ laid him on the green.” Wright heard wrong, thinking there were two slaying victims, the earl and “Lady Mondegreen.”"Bobbi's been pushing me to read Dreyer's English: An Utterly Correct Guide to Clarity and Style, and I think the linked column has pushed it to the top of my to-read pile.
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