catalytic converter

American  

noun

1. an antipollution device in an automotive exhaust system that contains a catalyst for chemically converting some pollutants in the exhaust gases, as carbon monoxide, unburned hydrocarbons, and oxides of nitrogen, into harmless compounds.

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catalytic converter British  

noun

1. Sometimes shortened to: catcon.  a device using three-way catalysts to reduce the obnoxious and poisonous components of the products of combustion (mainly oxides of nitrogen, carbon monoxide, and unburnt hydrocarbons) from the exhausts of motor vehicles

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Etymology

Origin of catalytic converter

First recorded in 1960–65

Example Sentences

The Police Department launched its investigation last July after noticing a “significant rise” in catalytic converter thefts.

From Los Angeles Times • Apr. 3, 2026

In 2023, the Los Angeles City Council voted to make it illegal to possess an unattached catalytic converter without proof of ownership.

From Los Angeles Times • Mar. 2, 2025

They also are checking to see if there are connections to other nearby catalytic converter thefts.

From Los Angeles Times • May 30, 2024

Many agencies don’t track catalytic converter thefts specifically, and other agencies vary in how they track them.

From Seattle Times • Apr. 1, 2024

It was boxy and angular, and it poured so much smoke out of its exhaust pipe, I was certain the Forges of some Dark Lord were firing deep within its catalytic converter.

From "Darius the Great Is Not Okay" by Adib Khorram