IPA: /ˌɒlɪˈɡɒpəlɪst/
KK: /ˌɑːlɪˈɡɒpəlɪst/
A person or company that is part of a market where a few sellers control the prices and supply of goods or services.
The oligopolist raised prices, knowing that the competition was limited.
Oligopolist → It is formed from "oligo-" (from Greek "oligos", meaning few) and "polein" (meaning to sell). An oligopolist is someone who sells in a market dominated by a few sellers.
Think of 'few' ('oligo-') sellers in a market — that's what an oligopolist is, someone who operates in a market with only a few competitors.
No commonly confused words.