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extraverted (adj.)[extraverted 词源字典]: in modern psychology, 1915, a variant of extroverted (see extrovert). Related: Extravert (n.), for which also see extrovert. There was a verb extravert in mid- to late 17c. meaning "to turn outward so as to be visible," from Latin extra "outward" + vertere "to turn."[extraverted etymology, extraverted origin, 英语词源]
extrovert (n.): 1916, extravert (spelled with -o- after 1918, by influence of introvert), from German Extravert, from extra "outside" (see extra-) + Latin vertere "to turn" (see versus). Used (with introvert) in English by doctors and scientists in various literal senses since 1600s, but popularized in a psychological sense early 20c. by Carl Jung. Related: Extroverted.
varus (n.): foot deformity in which the feet are extroverted, so that the inner ankle rests on the ground, while the sole of the foot is more or less turned outwards, 1800, from Latin varus "bent, bent outwards, turned awry, crooked," specifically "with legs bent inward, knock-kneed," of uncertain origin.
If the original meaning was 'with the legs opened', varus might be compared with vanus and vastus, and reflect *wa-ro- 'going apart, letting go'. In any case, none of the other etymologies proposed seems plausible. [de Vaan]
The use of classical varus and valgus, which denoted deformities of the legs, in modern medicine to describe deformities of the feet, was criticized by learned writers (see "Edinburgh Medical and Surgical Journal," July 1838).