Inhibitors are sometimes referred to as "negative catalysts" since they decrease the reaction rate.

Catalysts that slow the reaction are called negative catalysts, or inhibitors.

Positive catalysts speed up a reaction and negative catalysts slow down a reaction and possibly cause the reaction not occur at all.

Key concepts for energy profiles are activation energy, enthalpy change, exothermic and endothermic reactions, the rate of reaction, and positive and negative catalysts.