The definition of a scheme is a plot or a plan to achieve some action.(noun)
An example of a scheme is a plot to defraud your boss.
To scheme is to plot or plan to do something.(verb)
An example of scheme is when you and your friend meet to talk about how you are going to get away with skipping school.
See scheme in Webster's New World College Dictionary
Origin: L schema < Gr schēma (gen. schēmatos), a form, appearance, plan, akin to schein, echein, to hold, have < IE base *seĝh-, to hold, hold fast, conquer > school, Sans sáhas, power, victory, Goth sigis, Ger sieg, victory
See scheme in American Heritage Dictionary 4
Origin: Latin schēma, figure
Origin: , from Greek skhēma; see segh- in Indo-European roots.
Learn more about scheme