An eggcorn is a change in pronunciation and/or spelling which results in a new word or phrase that still makes a certain amount of sense, but deviates from the original. That is the difference between an eggcorn and a malapropism, which is an error in speech that results in something similar, but nonsensical.
“That is mind-bottling.”
“That man has old-timer’s disease.”
“I'll have a glass of skimp milk?
Eggcorns are completely or or nearly equal, from a phonetic
standpoint. The listener may not even realize that an eggcorn has
even been uttered.
Say, 'Texas has a lot of electrical votes'. This is not an eggcorn.
Although it sounds almost the same, any connection to the original
meaning of “electoral” is gone.
The term “eggcorn” was coined by linguist Geoffrey Pullum in 2003.
He used the example of a woman who said “egg corn” rather than
“acorn” which sound almost identical, depending on pronunciation.