Oligopoly is defined as an economic market where there is limited competition.(noun)
If there are only two phone service providers for an entire large city and people have to choose from among those two, this is an example of an oligopoly.
See oligopoly in Webster's New World College Dictionary
noun pl. oligopolies
Origin: olig(o)- + (mon)opoly
See oligopoly in American Heritage Dictionary 4
noun pl. ol·i·gop·o·lies
Origin: + (mono)poly.
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