[lesuorac]

For future people to look it up.

Monopoly is a single seller.

Monopsony is a single buyer.

[lesuorac]

Given how popular this has gotten I guess I should point out that it's wrong.

There isn't a single seller so the proper ones are

Oligopoly - Market with few sellers

Oligopsony - Market with few buyers

"few" really meaning that they have pricing power as opposed to 3 companies.