Marplot

Part of speech: noun

Pronunciation: /ˈmɑːplɒt/

Definitions

1. A person who ruins or spoils a plan or scheme through meddlesome interference or blundering action
2. A meddlesome individual whose clumsy involvement inevitably destroys others' carefully laid plans
3. Someone whose bungling meddling destroys carefully laid plans or schemes through thoughtless interference

Etymology: The name first belonged to a character, not a common noun. In Susanna Centlivre's comedy "The Busie Body," staged in 1709, Marplot is a meddling busybody whose well-intentioned interference keeps wrecking the schemes of the other characters. Audiences apparently found the name so fitting that it outlived the play and became a general term for anyone who spoils someone else's plans. The word is a straightforward compound of "mar," meaning to spoil or ruin, and "plot," in its older sense of a plan or scheme, which is the same "plot" that later came to mean the storyline of a story. Playwrights of the period often gave characters names that announced their personalities, and Centlivre's choice was blunt but effective: the man who mars the plot.

Synonyms: spoiler, interferer