When it comes to engines, the term "deleting" refers to the removal of one or more of the emissions control devices that the engine came with. When an emissions device is "deleted", the device and any other relevant components in question are physically removed and the engine is then re-tuned to run without said device.

"Deleting" is different from "defeating" in the sense that "deleting" refers to physically removing emissions devices, but "defeating" involves disabling emissions devices while leaving all of them in place on the engine. For example, an EGR (exhaust gas recirculation) cooler can be defeated by welding it shut in some spot or blocking it off from one or both ends by inserting a metal plate between the cooler and the exhaust or intake manifold. DPF's (Diesel Particulate Filters) can be defeated by being drilled out or by installing bypass pipes.

On Diesel engines, people who do deletes will typically remove EGR (Exhaust Gas Recirculation) systems and DPF's (Diesel Particulate Filters), as these two systems are infamous for drastically increasing a Diesel engine's fuel consumption.
Here in Michigan we no longer have any kind of emissions testing, which means that today you can find quite a few deleted Diesel trucks, and even some cars and SUV's, running around in the state.
by The_Anonymouse June 21, 2021
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This one is definitely worth my time and consideration... DELETED!!!
Homestar: Hey, where's Strong Bad? I sent him an invitation awhile ago!
Strong Sad: Maybe it got... De-le-ted!
by Donkey Kong Song December 05, 2003
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1. To remove a file or folder from a computer.
2. To delete data from a file (often text or numerical data).
3. To assassinate.
1. "You don't need those text files, just delete them."
2. "Delete the last two lines of that paragraph - they aren't really necessary."
3. "That guy has pissed me off for the last time. I'm going to hire someone to delete that motherfucker."
by Steve H. June 02, 2005
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The button that only Hillary Clinton can properly use, much to everyone else's disapproval.
Clinton will be the first F president. (that was meant to say female, but someone decided to delete the emale! jajajajajaja!)
by Intelligence001 July 17, 2016
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See also the following:
BALEETED
DELTEATED
DELTACO
Freaky D'ted
cheadeated
deedleated
MATT
meathead?
dltd
duh lee ted
teeteeted
bubs
diddly dee
repeated
733t3d
3-D movie
del monte
ddddddd
da cheated
diggity
beefeated
stupid word
Oh! Even I know what to do with this one. BALEETED! Wha'? Oh. Um...DELTEATED! No? Uhh...Deltaco?
by AlredyTryed January 06, 2004
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people who come on this site and go around getting things deleted at random, just because THEY dont agree with it. wich is pretty sad. Even more sad than making up a word to describe them.
"Those damned deleters got my definition of slapper deleted, maaan it took me a week to write that."
by Joe December 06, 2003
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