plotter vs contriver

plotter and contriver both are nouns.

Word	Noun	Adjective	Verb	Adverb
plotter	Yes	No	No	No
contriver	Yes	No	No	No

As nouns, contriver is a hypernym of plotter; that is, contriver is a word with a broader meaning than plotter:

Other hypernyms of plotter include deviser, planner.

plotter (noun)	contriver (noun)
an instrument (usually driven by a computer) for drawing graphs or pictures	a person who makes plans
a member of a conspiracy
a planner who draws up a personal scheme of action
a clerk who marks data on a chart