From mar (“to spoil, to ruin”) + plot (“plan”).
A compound of mar ‘to spoil, to ruin’ + plot ‘plan’
Proto-Indo-European *mers- ‘to annoy, disturb, neglect, forget, ignore’
Proto-Germanic *marzijaną ‘to disturb, hinder’
Old English mierran ‘to mar, disturb, confuse’
Middle English merren ‘to disturb, hinder, or prevent’
English mar
Old English plot ‘a plot of ground’
Middle English plot
English plot
The story
In earliest use as a character name in The Busie Body, by Susanna Centlivre, in 1709.
Today it means
noun Synonym of spoilsport, one who ruins other's plans or enjoyment of something.
Language periods are conventional ranges, not dates for this word.
Etymograph / marplot
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