Irregardlessness is a word for people to say "regardless". The word is created by having the prefix "ir" not/with/less and the suffix "ness" to increase the meaning. Hence, they cancel each other out, ending up with "regardless". You may use this to emphasise you don't care about the thing you are stating.
April: "Irregardlessness aint a word you fool!"

Tek: "Well it's a word now, irregardlessness of whether you like it or not ha ha!!"
by Tekah April 23, 2008
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Used by people who ignorantly mean to say regardless. According to webster, it is a word, but since the prefix "ir" and the suffx "less" both mean "not or with" they cancel each other out, so what you end up with is regard. When you use this to try to say you don't care about something, you end up saying that you do. Of course everyone knows what you mean to say and only a pompous,rude asshole will correct you.
Wife: "Irregardless is not a word, dummy"
Husband: "Kiss my ass bitch! I'm still going to the strip club tonight!"
by Dwayne Boyd August 12, 2005
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A word used by uneducated people intending to sound intelligent. Often, the defendant will use this word in court in an attempt to impress the judge and jury. Educated people notice and those who use this word instantly identify themselves to educated people as being uneducated. Educated people rarely correct them because it helps educated people more easily identify them if they are well groomed.
Uh... yes your Honor.... Irregardless of the the evidence, I was not the young man in the security video.
by sanjac1836 February 3, 2008
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An unnecessary mispronunciation of the word "regardless".
Guy 1: "Irregardless of what people think"...

Guy 2: (after punching Guy 1 in the face) "Say irregardless again! Say it!"
by Hank McDizzleson July 3, 2008
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A word you should never, ever use in front of your English professor.
Student: "But irregardless of that--"
English professor: "*thwack*"
by SurelyNotI November 23, 2005
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A double negative that while technically a word, is nearly always being incorrectly used instead of regardless. The people using this are usually pompous assholes who usually double down on irregardless being the correct word to use and are usually using it at the end of an email to be a passive aggressive shitheel.
Debbie: “Irregardless of what was said during that meeting I still need you to send me an up to date TPS report.”
John: “The correct word is regardless, and you can shove that TPS report up your ass.”
by Delicious Hamboning January 29, 2020
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