Hmm, I guess 'extrovert' is an acceptable spelling nowadays, even though it's the wrong Latin root.
But the author of this post goes even further, and uses both spellings in the same sentence!
In extravert-introvert pairs, extroverts report on greater closeness than introverts
That can't be right...
Google n-grams isn't all that sympathetic to my account, in showing a long history for 'extrovert' and suggests 'extravert' is actively dying out.
But the history may not go back far enough: https://blogs.scientificamerican.com/beautiful-minds/the-dif...
'Folklore has it that when Carl Jung was once asked which was the correct spelling—ExtrAvert or ExtrOvert—Jung's secretary wrote back something like, "Dr. Jung says it's ExtrAverted, because ExtrOverted is just bad latin."'
[...]
'According to the Oxford English Dictionary, "The original spelling 'Extravert' is now rare in general use but is found in technical use in psychology." That's correct. If you look at scientific journal articles, virtually every paper uses the spelling ExtrAvert.'
In my accent, at least, I pronounce the phrase 'extr_vert-introvert' with an open A, contrasting to the pursed O of introvert.
But if I say the word 'extr_verts', by itself, I pronounce it with an O, identical to 'introvert'.
It's difficult because for me, at least, in my accent, both are degrading to an unstressed vowel anyway, so it's a fine gradation.
It surely is. Caring about language (caring about anything, really) is an honest signal of status, whether you like it or not. Inevitably, some people will try to slave-moralize it away. If some social/ethnic/sex/... minority with inferiority complexes jumps on this bandwagon, suddenly you may find yourself caring about a thing whose ignorance some social scientists somewhere have found to be correlated with holy cows.
Proposed solution: stop caring about everything besides making all people feel good about themselves.
I'd think of extro- and intro- as looking out and in respectively. Extra- and intra- would be externally additive and internally additive; like a connection outside a defined group and inside such a group respectively.
tl;dr this was an edge case for me.
Historically the term was 'extravert' in psych literature. I feel like more technical usage probably still leans that way.
Adding Latin prefixes to "vertere" leads to such words as "to avert" (a- from Latin "ab-", meaning "from"), "to evert" (from "ex-" which means "out"; compare "extra-" above), "to invert" (from "in-" meaning "into"; compare "intro-" above); "reverse" (an adjective meaning 'opposite' from "re-" meaning "back"); "transverse" (an adjective meaning 'crosswise' from "trans-" meaning "across"); and so forth.
It's useful to compare "in-" vs "intro-" and "ex-" vs "extra-". The "-tra-" and "-tro-" infixes are essentially the same, but Latin writers and speakers inflected them historically. English inherited this in such words as "introduction", "extradition", "introspection", "extraordinary", and "extravagant".
Finally in modern biological and medicinal jargon it is common to use "intra-" (with an "a") as "within": "intracellular" (within cells; compare with "intercellular", "between cells"), "intradural" (within the dura mater in the spinal cord), "intramolecular" (e.g. internal forces holding together the shape of a molecule, or the atoms a molecule comprises), and so forth. Outside those technical settings, "intra-" is exceedingly rare. One example is "intramural" ("within the walls", usually used to describe a competition between different teams of students at a single school, however the word has use in medicine as well, the walls being those of a cell, blood vessel, or other hollow organ, and the medical use likely came first).