Marplot

Marplot \MAHR-plaht\ noun

: one who frustrates or ruins a plan or undertaking by meddling

 Usage:
“If Will hadn’t been such a nosy marplot,” said Darlene, “our plan to surprise Brenda with a party for her birthday might have gone off without a hitch.”

“It was obvious that President Uribe, who certainly is no marplot, was looking for a fracas when he preemptively revoked Hugo Chavez’s credentials to potentially negotiate a hostage swap.” — From a release by the Council on Hemispheric Affairs reported by the States News Service, January 10, 2008

Beginning in the 17th century, people liked to prefix “mar-” to nouns to create a term for someone who mars, or spoils, something. A mar-joy was bad enough, but even worse was a mar-all. Although today the word “plot” often carries an implication of secrecy or ill intent, the “plot” used in the formation of “marplot” simply meant “a plan for the accomplishment of something.” A marplot, therefore, can really mess up a perfectly good thing. The word may not have been invented by English playwright Susannah Centlivre, but it first surfaces in print in her 1709 play The Busy Body. That title refers to a character named Marplot, who misguidedly gets in the way of the lovers in the play.

Entry in Webster's Dictionary

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