Search: eat your heart out origin
Why: People on "RuPaul's Drag Race" say things like "Eat your heart out, Bob Mackie" all the time. To be honest, I don't even know what that's supposed to mean. Rizzo says it in Grease.
Answer: First, it's supposed to make the other person feel bitterness or pain as he longs for something out of reach.
The ancients believed that sorrow and envy silently "ate away" at the heart, "each sigh draining blood from the organ." In Henry VI, Shakespeare wrote:
Might liquid tears, of heart-offending groans,We still say someone who is grieving is "broken-hearted."
Or blood-consuming sighs recall his life,
I would be blind with weeping, sick with groans,
Look pale as primrose with blood-drinking sighs
By the beginning of the 20th century, "to eat your heart out" meant to pine, but you can yell it out as a cry of triumph if you give someone else a reason to envy you, like if you make a better ballgown as a drag queen than he ever did designing for a real lady (or a Cher).
Source: Expressions & Sayings, Phrases, Cliches, Expressions & Sayings
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