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.

---

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

---

Etymology

Origin of catalytic converter

First recorded in 1960–65

Example Sentences

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

Police launched an extensive search for the suspects, ultimately focusing on gang members tied to catalytic converter thefts in the region.

From Los Angeles Times • Sep. 12, 2024

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

From Los Angeles Times • May 30, 2024

No one can sell a catalytic converter without a driver’s license or state-issued photo identification and payments must be made by check and sent to the seller’s address at least three days after the sale.

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