Mondegreen

Our report of a relative who, as a child, thought the classic version of the Lord's Prayer began "Our father, a chart in heaven, Harold be thy name" stated that this type of mistake is known as an eggcorn. A number of readers have suggested that instances like this in which a whole phrase rather than just a word is misheard, should be called mondegreens rather than eggcorns.

Source: wiktionary

The title lyric ["Bei Mir Bistu Shein"], the only part of the original Yiddish preserved by Cahn, was a mondegreen waiting to happen—“My Mere Bits of Shame” and “My Beer, Mr. Shane” were among the earliest recorded mishearings—but the language barrier didn't […]

Source: wiktionary