I find the etymological explanation of this phrase to be woefully inaccurate. The most glaring error is the simple fact that neither "vertica" nor "vicinne" are Latin words. "Vertex," a masculine noun of the third declension (declined, vertex, verticis, etc.) may have been mistaken as the root of the nonexistent "vertica." As for "vicinne," your guess is as good as mine. My proposed correction would read:
The phrase "vice versa" is a Latin ablative absolute involving the masculine third declension noun "vicis" (arrangement, order, position, etc.) - abl. sing. = "vice" - and the feminine ablative singular of the perfect passive participle "versus," from the verb "verto" (turn, reverse, etc.). The phrase is literally translated, "the position having been reversed."
Added See Also links 22:13, 5 February 2006 (UTC) Cy21