Eggcorn Forum

The inelegant term “brain fart” has its own wikipedia entry:

A brain fart (may be jocularly derived from “brainstorm”)[1] is slang for a special kind of abnormal brain activity which results in human error while performing a repetitive task,[2][3] or more generally denoting a degree of mental laxity or any task-related forgetfulness, such as forgetting how to hold a fork. Tom Eichele, a neuroscientist at the University of Bergen in Norway, was part of an international team of researchers who identified activity detectable in brain scans up to thirty seconds before a mistake, which could be referred to as a brain fart, occurs.

And in the etymology section:

The derivation of the term may be related to the term “brain infarction”; however, a more likely etiology is the direct comparison of the episode of forgetfulness escaping one’s brain without check to the accidental production of flatus.

This potential eggcorn was identified by two earlier commenters, including one on the Wikipedia talk page.

I will take this opportunity to comment on one of the newest eggcorns: Brain fart. It is correctly a brain farct. Unfortunately, those who have not come from a clinical arena do not know that ‘farct’ is actually a form of infarction. I, frankly, find ‘brain fart’ to be an offensive term.
eggcorn thread

Brain fart
It has long been my unexamined assumption that the term “brain fart” is an eggcorn derived from the medical term infarct or Infarction, a small area of dead tissue caused by circulatory blockage that may occur in the brain or elsewhere. This might well be my own folk etymology, however any confirmatory evidence would be appreciated and could enable this, if true, to be added to the article. 87.81.230.195 (talk) 17:22, 20 February 2010 (UTC)
Wikipedia Talk page, fart

I think the ngram provides some pretty solid support for this etiology. There’s no such thing as a “farct”. On the other hand, my rapid pronunciation of brain infarct sounds very close to brain farct. Calling it a brain fart might have been originally been a joke, but now it is spreading widely and it looks very likely to overtake the original.

The intermediate stage, from 2001:

I very well may have confused that info so please disregard my prior post until I research it further. Sorry….I may have misstated…..other words for having had a brain farct! :)
38 posted on 2001-10-22, 2:16:02 AM by MistyCA
http://www.freerepublic.com/focus/f-news/553574/posts

Finally, larrybob has provided the best explanation yet. “Perhaps “operator air” indicates a gaseous condition:”

“I’ve lost the first one I made to because of operator air (brain fart), but I made two more.”
http://eggcorns.lascribe.net/forum/view … hp?id=5662